As always Professor, you have presented an extremely thorough and easy-to-follow explanation of a complicated mechanism. Thank you for it and all your videos.
I watched multiple videos about Prius transaxle and understood something about only here. Planetary gear is a simple stupid and reliable solution and is result of an ingenious approach.
I find the control of both MG's really impressive! in EV mode both have to spin synchronized, at 1.014:1, so they don't jerk the IC engine forwards or backwards , as far as i can tell there's nothing to lock it, no brake no pawl.. Thank you for taking the time to do these videos.
If I understand the question perhaps differently, I can offer an alternative answer. The reason the issue asked is not a problem because the engine speed is tightly controlled at all times since both MG1 and 2 are permanent magnet servo motors with positional feedback that can hold any stationary position or any precise RPM with high torsional and positional angular rigidity. During starting of the ICE there is a delicate torque and speed balance between all three units (and the wheels) that allows starting the engine without causing driver-perceptible "bumps" to appear in the car's forward motion. The per-cylinder starting and firing torque pulses are neatly countered by the fast servo response of the two MG units with only backlash in the gearing being an unavoidable but minor detriment. This is the brilliance of Toyota's HSD concept. By accepting the expense of a few very pricey parts (the motors and drive electronics,) they have vastly simplified the overall mechanics and controls of the hybrid system including little details like how to smoothly bring the ICE on line. There's no starter motor, no conventional alternator and not even a conventional neutral. The expense pays off as the motors are utilised both for electric propulsion, generation, and to effect the ICE's gearing to the wheels. Although the HSD by itself is expensive, other items are not needed or are relatively cheap. It's all incredibly simple in concept and construction, yet highly flexible in operation.
Many thanks - I have watched the video - I must admit I thought I had a CVT transmission. I am pleased I haven't. Planetary Gears are fascinating to me.
Hi. Thanks for your videos. Im a proud owner of a 2014 Lexus CT200h with a P410 transaxle. It is interesting to see how the system operates through an app called Hybrid assistant that i connect to my car via an OBD adaptor. The system always tries to keep the engine (when running) at 90% load where it is achieving its maximum BSFC. There are situations when charging the battery that both MG's become generators while the engine is pushing the car and the the two MG's at the same time. When applying more acceleration through the pedal it reduces the amount of charging load on MG2 and the engine torque goes to the wheels, thus accelerating while at the same time keeping the engine load at 90%
Excellent video. Just bought a hybrid and was wondering how this all works in detail. Best video for information and to learn. I would love to join a course. Great work.
What's interesting about this model transaxle is that the MG1/ IC engine / power split unit as a group is geared significantly taller to the wheels, while MG2 is much the same despite the additional planetary set. A useful comparative calculation would be the IC gear ratio to the wheels at 3 conditions: MG1=0, and both plus and minus maximum RPM.
With MG1=0 RPM, the ICE would overdrive the counter-drive gear with a ratio of 0.2778. If the ICE RPM were 1000, the counter-drive gear RPM would be 3600 RPM. MG2 would be rotating 2.636 times slower at 1366 RPM, which is equal to 10.8 mph on a P410. FYI, at 108 mph, with the ICE off, MG2 would be at its maximum speed of 13500 RPM, MG1 would be at -13500 RPM. At that same 108 mph with the ICE at 3750 RPM, MG1 would be totally stopped. At 108 mph with the ICE at its maximum RPM of 5500, MG1 would be at 6121 RPM. Fun stuff! Have a good day
OK, it seems the ICE/MG1 combo does have significantly higher gearing over the wheels than earlier HSDs. It's hard to get my head around why, but there must be gains to be had by doing this. Certainly losses are lower when electrical power conversion between MG1 and MG2 is minimal (essentially MG1=0 rpm) and I've always thought that condition would be focused around highway speeds where unavoidable aerodynamic losses become predominant. I believe the earlier HSDs were about 60 mph at MG1=0.
Excellent videos as usual. Thank you. But motor speed reduction gear set ! You are thinking of those words in reverse. The gearset does reduce the speed. Not of the motor, but of the drive output. Haha. It's always called a speed reducer. Just that adding the word motor to the front confuses things.
Great explanation. Please explain why the transaxle is only rated at 105 lb. ft of torque and struggles to break under 10 sec 0 to 60, since the MG2 puts out over 400 lb ft with the gear reduction. Thank you
Dear Professor Kelly, How is MG1 connected to planet carrier shaft and how is it locked to flying wheel? What is the exact mechanism of regulating ice torque (I get the electrical part, but do not get the mechanical one - MG1 to shaft bonding)? Thank you very much in advance.
@WeberAuto At 19:35 in the video, you mention the 2012 - 2015 plug-in version being capable of driving up to 61 mph in EV mode. Is that only specific to the plug-in model? I do a lot of freeway commuting in thick traffic and the average speed is often less than 60 mph. If I had the standard non-plugin 2010-2015 3rd gen version, is the combustion engine assisting or is it all electric? Thanks!
Hi Prof, and many thanks for the explanation. Question: you explained how the planetary carrier of the motor speed reduction gear is held stationary, which would mean that MG2 and the wheels must always turn together, albeit with different ratios. Is there a control mechanism to release the motor speed reduction planetary carrier and thus effectively disconnect MG2 from the wheels? That might be more efficient when cruising at 100kph with direct drive from engine to wheels, without having to power MG2 as well. That might also explain why the Toyota manual claims that it reduces the speed of MG2.
I'm afraid you appear confused about the term "motor speed reduction" in this case. It seems obvious that the intent is to replace the former MG2 with a lighter, smaller, and probably more powerful motor. This is achieved by the use of a much faster revving motor requiring less torque to produce similar power. (~2.6x less torque @ ~2.6x greater speed) Of course, to preserve the series mounted motor architecture, the shaft speed of the much faster motor must be reduced to a speed similar to the output of the former motor, hence the "motor speed reduction" gearset. It is the speed at which MG2 drives the counterdrive gear that is reduced, not the speed of either of motor. It may be helpful to view the MG2-gearset combination as a single unit replacing the former motor. It should be noted that the dramatic change in ratio of the speeds of MG1 and MG2 does not result in a reduction in speed of MG1, but is the result of the much higher speed of MG2. Thank you
I enjoyed your video, great explanation. I have a problem with my flywheel on my Prius v. It's having trouble engaging the transmission at low engine rpm (1300-2000) creating vibration and rattle noise (diagnosed by Toyota). The vehicle still drives somewhat ok, it's just quite annoying. Will the flywheel eventually completely fail, or can I drive around like this without doing further damage? It's kind a pricey to repair, so just wondering if I can stretch it out? Thanks.
P410 on my CT200H. If I only use the transmission lock (P) on a very slight slope on my drive, am I going to harm the mechanism over time? I tend to worry about using both the pedal operated parking brake and "P" as the system could be locked in torsion somehow.
WeberAuto these are the nest videos I’ve seen on show the Prius transmission! I am afraid that I’m still confused as to how the “gear ratio” changes while you accelerate from let’s say 10mph up to 70mph??? It still seems to me that the only way to make the tires on the car rotate faster is to literally rotate the engine and MG2 faster? I’m hopefully buying a 2012 Prius plug-in this week! Any help is much appreciated thanks 🙏🏼
Professor, have you ever ran into a common problem with code 526/614? I have a 2012 Toyota Prius V and I have this code present. I have replaced the Inverter/Converter and still same code comes up?? I read online that 614 is narrowed down to a problem in inverter/converter. But upon further research into this 614 it maybe several other issues I am stumped. Any input maybe helpful. Thanks!
So after this video I understood that Prius has no CVT. PSD is mistakenly called CVT. So here's the question: what would happen if you fill CVT fluid instead of ATF WS? Would it do a damage to transaxle after 5k miles? Thank you for your answer.
I have a 2010 Prius and wondering, as you are most qualified to answer, should I do a drain and refill the transmission fluid? Toyota manual (and dealers) says no while many advise at 30-60k miles. I understand the Prius Transaxle has a very good reliability rating making me think leave alone as not changed yet at 115k miles. Thank you in advance for your opinion.
Hi, I am and I have an issue with my prius 2010. When my battery (two lines) is low I had a nocking and it was disappear after the battery was getting to three lines. Now the nocking started to be when the battery is almost full and the IC engine start. If this is on a steep hill the nicking is making the car to have a nicking during driving (like an old clutch for the classic cars). we had take the engine and gear box down. The dumper does not a big noise, the signs are not visible and if you are moving the dumper left and right quickly another nocking appear in the gearbox. I kindly ask you to help me. What can be and how I can solve the issue? For more information (pictures and videos) please do not hesitate to contact me in order to set, if is possible a meeting. Many thanks, Traian
Dear professor Kelly, thank you for your videos and your work. They are very helpful. But could you please explain why you emphesize the situation when MG1 rotats the same speed as engine (planet carrier)? This situation is nothing special for the hibrid system. Part of the torque could be used for recharching the battery like in most of other cases and not all torque must be transfered to the wheels what yuo suggest. It is only special case mechanical - the planetary gear does not increase or decrease the rotary speed of engine. It could be special case only if the parts of planetary gear would be blocked mechanical. Then the entire torque from engine could be transfered mechanical to the wheels. However it would be still possible to take part of the torque by MG1 and transfer to the battery or MG2. Ther is a situation when the entire torque from engine is transfered mechanical to the wheels - when MG1 does not rotate at all, MG2 could only help by gaining energy from batteries. And it is not true that MG2 is always the main source of torque. In the situation when MG1 does not rotat, MG2 usually does not create torque. There is interesting video on youtube how the system works in practice th-cam.com/video/H1xZHgf9bAM/w-d-xo.html They are situation when engine works, rpm of MG1=0, torque of MG2=0 and torque of MG1 has a quite big minus value what means that the entire torque from engine is transfered mechanical.
well excellent description.sir if Car is running at 50Kmh and Ntire=417.7295rpm and engine at 0 rpm then how the RPMof MG2 is calculated?and what would be the RPM of MG1.
Hello professor, I have 3rd Gen prius, and having error code P0AA6 every time I connect the AC power cable from inverter converter to AC compressor (orange cable) I replaced that cable and the compressor as well and still getting this error only when I connect the compressor to inverter converter module, what is the best way to diagnose this issue? Thanks in advance
Thank you for an intelligent yet easy to follow video Professor! My question for you is that Toyota's current policy is that the gearbox oil should never be changed during the lifetime of the car. What is your opinion of that policy and would you recommend that the gearbox is serviced with an oil change?
Hi, if you read the maintenance schedule you will find that there is a service interval for the transmission fluid, but it varies with how the vehicle is driven. The ones I have read have it being changed at anywhere from 90k-130k miles on cars, and as low as 50k miles on trucks. Lifetime is a relative term, it does not mean as long as you can keep the vehicle running, it is a sales term to make people feel good in thinking that it never needs to be serviced. Of course, if the transmission ever leaks or malfunctions, the fluid will probably need to changed as part of the diagnostic work. I hope that helps.
thankyou Mr Kelly just a question about relative compression on a prius not using a techstream scanner being there is no conventional starter. I'm wondering if there is a way to get the MG motor to crank the ICE cutting off fuel and putting FIRSTLOOK sensor in tail pipe and looking at waveform on scope? thanks again happy new year
@@WeberAuto I thought there was a series of steps that you perform to make the motor run, It is not recommended to drive with it. (prius maintenance mode) as follows: Prius Maintenance Mode Toyota Prius Gen II I4 1.5L Hybrid Synergy Drive into maintenance mode. Second generation Prius model years are 2004, 2005, 2006, 2007, 2008 & 2009. To activate Inspection Mode on the Prius, the following steps must be completed within 60 seconds: 1. Keep your foot off the brake pedal. Then "power up" the car by pressing the POWER button twice. 2. Next, floor the gas pedal and fully release it twice. 3. Depress the brake pedal and keep it depressed with your left foot for the rest of this procedure. 4. Shift into Neutral, then floor the gas pedal and fully release it twice. 5. Shift back into Park, then floor the gas pedal and fully release it twice. 6. Now the HV warning light on the multi-information display (TV-like screen) should flash. This warning light has the silhouette of a car with an exclamation point (!) on it. 7. Push the POWER button. The engine should start and continue idling at about 1000 rpm. 8. Press the POWER button one more time to shut off the engine. This last step also deactivates Inspection Mode. The important thing to remember here: Never, ever road-test a Prius while it's still in Inspection Mode!
Dear Professor Kelly, thank you very much for this very informative insight to the Prius Gen3 Transaxle. As far as i understood from it, the transaxle fluid (oil) does absolutely not come in contact with the stators and motors of this transmission? I'm asking this because in some forums people state that the transmission fluid need to have some dielectric (isolating) properties to make sure that the windings of the stators and motors are not getting shorted. This always seemed nonsense to me. Am i right?
Thank you! The stators are cooled by the transmission fluid running over them. The stator windings are insulated and will not be shorted by the fluid. The rotors are just magnets in a laminated case. I hope that helps
hello Mr kelly I really enjoy your videos and have watched them many times as I have taken a few of these trans apart. What I am seeing as far as trans fluid is it seems to not be pumped into the stator area and confined to the differential/planetary gear box as lubricant. Looks to me like only inverter fluid is routed around the outside of the stators in sealed channels and that is used as stator coolant not the trans fluid. Please correct me if I am wrong. And thank you very much for taking the time to do these tutorials.
Thank you! That is true for the 1st and 2nd generation transaxles, but the 3rd and later models also have sling lubrication with oil catch tanks that direct gravity fed fluid to the bearings, gears, and both stator windings (for additional cooling).
Can you tell me what are the dimensions(inner and outer diameter)of the counter driven gear bearings, i belive one of them is worn because my car makes a noise while i drive and i have checked it is not a wheel bearing noise.
Is there room in the trans-axle to reverse the drive direction of the forward gears at the final? such as installing this unit in a rear wheel drive vehicle which the tires sit in front of the engine?
@@WeberAuto I'm not sure my question was understood, as an example - in many differentials there's room to flip the ring gear and carrier 180 side to side and reverse the final output.
@@gehidore No. If MG1 spins faster than the ICE, underdrive gear is obtained. If MG1 spins slower than the ICE, overdrive gear is obtained. If MG1 spins the same speed as the ICE, direct drive gear is obtained.
At cruising speed, low engine rpm, mg1 have to reverse rotation to achieve low engine rpm. What makes mg1 to rotate in reverse? Is it powered by the high voltage battery or mg2 providing electric power to mg1? Thanks.
Around time frame 24:17 to 24:30 you stated that all the torque from the ICE is transferred to the ring gear when Wice = Wmg1, but actually this is not true. It's a subtle point, but an important one. If Wmg1 (angular velocity of MG1 in rad/s) = Wice and both are > 0 rad/s, then Wice = Wring = Wmg1. Now let's say T (torque) of ICE is 397NM. This comes from P/W=T or 50.022KW/126rad/s = 397NM. So the total torque is 397NM (ice) = Tmg1 + Tring, Now Tmg1 = Tice/(1+p) where p = Nr/Ns or 78/30 = 2.6. So Tmg1 = 110.278NM and so this leaves 397NM-110.278NM or 286.722NM going to the ring gear. As you can see ICE's torque (397NM) doesn't all go to the ring gear. Thanks.
If electric power from the Ni Metal hydride battering is use to make MG1 spin at the same speed as the IC engine, maximum torque from the engine is applied to the drive shaft and the wheels (because the planetary gear set, the sun, planets, and ring, all turn as one). I'm not clear about what happens when MG 1 is spinning at a DIFFERENT speed than the speed of the IC engine - about what happens if electric power from the Ni metal hydride battery to MG1 makes MG1 spin Slower than the IC engine. And is it correct to assume that MG1 cannot spin Faster than the IC engine? So if MG1 spins at the same speed as the engine, maximum torque from the engine is applied to the drive shaft and the wheels. If MG1 spins slower than the engine is less torque applied to the wheels from the engine? What about if the engine is turning but MG1 is not turning? I'm thinking that MG1 does not actually supply torque to the wheels, it is used as a generator to charge the Nickel Metal hydride battery, and as a motor to start the IC engine and I'm thinking MG2 is the only one of the two MG devices that supplies torque to the wheels. Is that correct? I'm getting confused. I saw the engine being turned (actually the flywheel being turned), MG1 was locked up to the engine, they were spinning together, and yet the drive shaft not moving. So it is not always true that if MG1 is spinning at the same speed as the engine, that the engine is supplying torque to the drive wheels.
Hi I just replaced 3Gn engine and I’m having problem to drive ones I put the car on drive won’t go I just replaced the engine that’s all plus I did drain the fluid from the transmission and bought brand new fluid from Toyota dealership that is recommended for Toyota Prius and I put it in there and I can drive the vehicle at all any help please plus some people saying that I have to mark the flywheel to certain position before i put the clutch plate thanks
Hi, You do not have to mark the flywheel, but the torque limiting clutch disk does have an engine side and a transmission side. I recommend checking for trouble codes. Make sure the electronic parking pawl motor is connected to the wire harness as well. Maybe it is stuck in Park. Best wishes.
It really should never be any reason for them to fail. The motors cannot be mounted externally because they are lubricated by a oil bath inside the casing, as well as temperature controlled.
So strange that the ICE always starts when speed is over 43 MPH even when no power is needed, like when going down a hill and accelerating due to gravity.
Lexus brags with the fact that the CT200h has a sport mode with features like 650 Volts hybrid system for better acceleration and mid-range response. I know that they use 500 Volts for the Prius. Can you please explain the quirks of that car?
Hi, the third generation Prius 2010-2015 and the Lexus CT200h 2011-2017 both use the same P410 transaxle, engine, battery, inverter converter, and system voltages (650V). The 2nd generation Prius used 500V. The sport mode is nothing more than a throttle response variation making it seem like it has more power. The CT200h is 45-90kg (100-200 lbs) heavier then the Prius depending upon the vehicle option package. I hope that helps.
Hi Sir again I'm RAMZI . please can you tell me again how can i find pin 1 and pin 3 on INVERTER HYBRID TOYOTA GEN4 P610 ON Inverter its 2 connecters one (24pin ) another connector (13 pin ) pleas if you tel me hwo can I connect power 12 volt to run InverterI will be very grateful to you
@@WeberAuto Hi. Im using an android app called hybrid assistant that it is connected to the hybrid system via an OBD device. In highway speeds of around 60 mph the MG2 becomes a generator and the MG1 provides traction in cooperation with the ICE. The MG2 rpm was 7700, ICE was 1430 rpm and MG1 was at 2480 rpm. MG2 was generating 8.2 kw of power, ICE 13 kw and MG1 6.4 kw of which 1.7 kw was coming from the battery.
@@WeberAuto Prof. Kelly, Do the stators are exposed/submerged in the ATF? I am wondering if it is cooled by ATF because it has much less problems than Gen2 Prius on the burned stators.
As always Professor, you have presented an extremely thorough and easy-to-follow explanation of a complicated mechanism. Thank you for it and all your videos.
Dear Professor Kelly, Extremely grateful for your wonderful presentations. I watched all your videos in one go. Please keep up the good work
Thank you!
I'm getting a Prius soon, and these videos are a massive help in understanding the inner workings of these wonderful vehicles! Thank you!
Thank you, I am glad they are helpful.
I believe that this drive train is in my 2013 Lexus CT200h. Thanks for a very clear explanation.
Yes it is. Thanks for watching
All pretty interesting stuff. I'm always amazed at this technology. Thank you for this explanation.
Thank you very much
This video is absolutely fantastic! Thanks so much and all in one take 👍 this truly is engineering explained!
Awesome! ...Thank you for sharing your in depth knowledge about this subject it really helps many people like me get into EV conversions
Glad it was helpful!
Thank you very much Professor Kelly!
Thank you!
I watched multiple videos about Prius transaxle and understood something about only here. Planetary gear is a simple stupid and reliable solution and is result of an ingenious approach.
Thank you professor Kelly. Awesome presentation.
I really enjoy this channel,ever explanation is clear and interesting
Thank you
Fascinating. The Parallel Hybrid system is sure unique design to go in the history book.
Thank you for this comprehensive video on Toyota's HSD. Very competent explanations, chapeau.
Thank you!
I find the control of both MG's really impressive! in EV mode both have to spin synchronized, at 1.014:1, so they don't jerk the IC engine forwards or backwards , as far as i can tell there's nothing to lock it, no brake no pawl..
Thank you for taking the time to do these videos.
Thank you! There is a pawl. See my P410 Deep Dive video for details. th-cam.com/video/5lg6yC5_-Bs/w-d-xo.html
If I understand the question perhaps differently, I can offer an alternative answer. The reason the issue asked is not a problem because the engine speed is tightly controlled at all times since both MG1 and 2 are permanent magnet servo motors with positional feedback that can hold any stationary position or any precise RPM with high torsional and positional angular rigidity. During starting of the ICE there is a delicate torque and speed balance between all three units (and the wheels) that allows starting the engine without causing driver-perceptible "bumps" to appear in the car's forward motion. The per-cylinder starting and firing torque pulses are neatly countered by the fast servo response of the two MG units with only backlash in the gearing being an unavoidable but minor detriment.
This is the brilliance of Toyota's HSD concept. By accepting the expense of a few very pricey parts (the motors and drive electronics,) they have vastly simplified the overall mechanics and controls of the hybrid system including little details like how to smoothly bring the ICE on line. There's no starter motor, no conventional alternator and not even a conventional neutral. The expense pays off as the motors are utilised both for electric propulsion, generation, and to effect the ICE's gearing to the wheels. Although the HSD by itself is expensive, other items are not needed or are relatively cheap. It's all incredibly simple in concept and construction, yet highly flexible in operation.
Many thanks - I have watched the video - I must admit I thought I had a CVT transmission. I am pleased I haven't. Planetary Gears are fascinating to me.
Thanks for your feedback!
Wow!, amazing too many gears, I never thought of that, thanks for sharing this video.
Thank you!
Awesome video; you answered so many questions ive always had about the Prius engine/planetary gears/ transmission...thank you
Hi. Thanks for your videos. Im a proud owner of a 2014 Lexus CT200h with a P410 transaxle. It is interesting to see how the system operates through an app called Hybrid assistant that i connect to my car via an OBD adaptor. The system always tries to keep the engine (when running) at 90% load where it is achieving its maximum BSFC. There are situations when charging the battery that both MG's become generators while the engine is pushing the car and the the two MG's at the same time. When applying more acceleration through the pedal it reduces the amount of charging load on MG2 and the engine torque goes to the wheels, thus accelerating while at the same time keeping the engine load at 90%
Nice ! Gets better ad better with each vid !
Thank you!
Excellent video. Just bought a hybrid and was wondering how this all works in detail. Best video for information and to learn. I would love to join a course.
Great work.
Thank you!
Great explanation! Thank you very much
Thank you!
Thanks Professor Kelly.
Regards,
Ramish.
Thank you
Brilliant presentation. Thank you.
Excellent presentation.
This video is greaaaaat thanks!!
Just imagine how crazy gen3 Prius would be if it had gen2's MG 2.
It would burn rubber!
What's interesting about this model transaxle is that the MG1/ IC engine / power split unit as a group is geared significantly taller to the wheels, while MG2 is much the same despite the additional planetary set. A useful comparative calculation would be the IC gear ratio to the wheels at 3 conditions: MG1=0, and both plus and minus maximum RPM.
With MG1=0 RPM, the ICE would overdrive the counter-drive gear with a ratio of 0.2778. If the ICE RPM were 1000, the counter-drive gear RPM would be 3600 RPM. MG2 would be rotating 2.636 times slower at 1366 RPM, which is equal to 10.8 mph on a P410.
FYI, at 108 mph, with the ICE off, MG2 would be at its maximum speed of 13500 RPM, MG1 would be at -13500 RPM. At that same 108 mph with the ICE at 3750 RPM, MG1 would be totally stopped. At 108 mph with the ICE at its maximum RPM of 5500, MG1 would be at 6121 RPM.
Fun stuff! Have a good day
OK, it seems the ICE/MG1 combo does have significantly higher gearing over the wheels than earlier HSDs. It's hard to get my head around why, but there must be gains to be had by doing this. Certainly losses are lower when electrical power conversion between MG1 and MG2 is minimal (essentially MG1=0 rpm) and I've always thought that condition would be focused around highway speeds where unavoidable aerodynamic losses become predominant. I believe the earlier HSDs were about 60 mph at MG1=0.
Yes, at 60 mph the speed of MG1 is 0.97 RPM at 2396 ICE RPM on the P111, 2422 ICE RPM for the P112
Excellent videos as usual. Thank you. But motor speed reduction gear set ! You are thinking of those words in reverse. The gearset does reduce the speed. Not of the motor, but of the drive output. Haha. It's always called a speed reducer. Just that adding the word motor to the front confuses things.
Thanks. I did have that backwards
Great explanation. Please explain why the transaxle is only rated at 105 lb. ft of torque and struggles to break under 10 sec 0 to 60, since the MG2 puts out over 400 lb ft with the gear reduction.
Thank you
Dear Professor Kelly,
How is MG1 connected to planet carrier shaft and how is it locked to flying wheel? What is the exact mechanism of regulating ice torque (I get the electrical part, but do not get the mechanical one - MG1 to shaft bonding)?
Thank you very much in advance.
@WeberAuto At 19:35 in the video, you mention the 2012 - 2015 plug-in version being capable of driving up to 61 mph in EV mode. Is that only specific to the plug-in model? I do a lot of freeway commuting in thick traffic and the average speed is often less than 60 mph. If I had the standard non-plugin 2010-2015 3rd gen version, is the combustion engine assisting or is it all electric? Thanks!
I was referring to the Plug-in model. All electric until 61 mph under light loads
@@WeberAuto Thank you so much! I love your videos!
Hi Prof, and many thanks for the explanation. Question: you explained how the planetary carrier of the motor speed reduction gear is held stationary, which would mean that MG2 and the wheels must always turn together, albeit with different ratios. Is there a control mechanism to release the motor speed reduction planetary carrier and thus effectively disconnect MG2 from the wheels? That might be more efficient when cruising at 100kph with direct drive from engine to wheels, without having to power MG2 as well. That might also explain why the Toyota manual claims that it reduces the speed of MG2.
There is no mechanical disconnect. The electric system can effectively leave the stator's circuits open so the rotor freewheels.
I'm afraid you appear confused about the term "motor speed reduction" in this case. It seems obvious that the intent is to replace the former MG2 with a lighter, smaller, and probably more powerful motor. This is achieved by the use of a much faster revving motor requiring less torque to produce similar power. (~2.6x less torque @ ~2.6x greater speed) Of course, to preserve the series mounted motor architecture, the shaft speed of the much faster motor must be reduced to a speed similar to the output of the former motor, hence the "motor speed reduction" gearset. It is the speed at which MG2 drives the counterdrive gear that is reduced, not the speed of either of motor. It may be helpful to view the MG2-gearset combination as a single unit replacing the former motor.
It should be noted that the dramatic change in ratio of the speeds of MG1 and MG2 does not result in a reduction in speed of MG1, but is the result of the much higher speed of MG2.
Thank you
I enjoyed your video, great explanation. I have a problem with my flywheel on my Prius v. It's having trouble engaging the transmission at low engine rpm (1300-2000) creating vibration and rattle noise (diagnosed by Toyota). The vehicle still drives somewhat ok, it's just quite annoying. Will the flywheel eventually completely fail, or can I drive around like this without doing further damage? It's kind a pricey to repair, so just wondering if I can stretch it out? Thanks.
P410 on my CT200H. If I only use the transmission lock (P) on a very slight slope on my drive, am I going to harm the mechanism over time? I tend to worry about using both the pedal operated parking brake and "P" as the system could be locked in torsion somehow.
WeberAuto these are the nest videos I’ve seen on show the Prius transmission!
I am afraid that I’m still confused as to how the “gear ratio” changes while you accelerate from let’s say 10mph up to 70mph???
It still seems to me that the only way to make the tires on the car rotate faster is to literally rotate the engine and MG2 faster?
I’m hopefully buying a 2012 Prius plug-in this week! Any help is much appreciated thanks 🙏🏼
See my RAV4 hybrid video for a better description of how the system varies the gear ratios. th-cam.com/video/O61WihMRdjM/w-d-xo.html
Professor, have you ever ran into a common problem with
code 526/614? I have a 2012 Toyota Prius V and I have this code present.
I have replaced the Inverter/Converter and still same code comes up??
I read online that 614 is narrowed down to a problem in inverter/converter.
But upon further research into this 614 it maybe several other issues I am stumped.
Any input maybe helpful. Thanks!
So after this video I understood that Prius has no CVT. PSD is mistakenly called CVT. So here's the question: what would happen if you fill CVT fluid instead of ATF WS? Would it do a damage to transaxle after 5k miles? Thank you for your answer.
I have a 2010 Prius and wondering, as you are most qualified to answer, should I do a drain and refill the transmission fluid? Toyota manual (and dealers) says no while many advise at 30-60k miles. I understand the Prius Transaxle has a very good reliability rating making me think leave alone as not changed yet at 115k miles. Thank you in advance for your opinion.
Just did fluid drain and refill. Fill tube run from behind engine worked great. Just over 3 quarts out and almost 3.5 quarts went back in.
Hi, I am and I have an issue with my prius 2010. When my battery (two lines) is low I had a nocking and it was disappear after the battery was getting to three lines. Now the nocking started to be when the battery is almost full and the IC engine start. If this is on a steep hill the nicking is making the car to have a nicking during driving (like an old clutch for the classic cars). we had take the engine and gear box down. The dumper does not a big noise, the signs are not visible and if you are moving the dumper left and right quickly another nocking appear in the gearbox.
I kindly ask you to help me. What can be and how I can solve the issue?
For more information (pictures and videos) please do not hesitate to contact me in order to set, if is possible a meeting.
Many thanks,
Traian
Dear professor Kelly, thank you for your videos and your work. They are very helpful. But could you please explain why you emphesize the situation when MG1 rotats the same speed as engine (planet carrier)? This situation is nothing special for the hibrid system. Part of the torque could be used for recharching the battery like in most of other cases and not all torque must be transfered to the wheels what yuo suggest. It is only special case mechanical - the planetary gear does not increase or decrease the rotary speed of engine. It could be special case only if the parts of planetary gear would be blocked mechanical. Then the entire torque from engine could be transfered mechanical to the wheels. However it would be still possible to take part of the torque by MG1 and transfer to the battery or MG2. Ther is a situation when the entire torque from engine is transfered mechanical to the wheels - when MG1 does not rotate at all, MG2 could only help by gaining energy from batteries. And it is not true that MG2 is always the main source of torque. In the situation when MG1 does not rotat, MG2 usually does not create torque. There is interesting video on youtube how the system works in practice th-cam.com/video/H1xZHgf9bAM/w-d-xo.html They are situation when engine works, rpm of MG1=0, torque of MG2=0 and torque of MG1 has a quite big minus value what means that the entire torque from engine is transfered mechanical.
Hi John , what happens when the vehicle is put in "power mode" ?? Are both MG's contribute to the final drive gear ??
well excellent description.sir if Car is running at 50Kmh and Ntire=417.7295rpm and engine at 0 rpm then how the RPMof MG2 is calculated?and what would be the RPM of MG1.
MG2 is directly connected to the tires through gears, it can be calculated by the gear ratio of the final drive and the counter gear
Hello professor, I have 3rd Gen prius, and having error code P0AA6 every time I connect the AC power cable from inverter converter to AC compressor (orange cable) I replaced that cable and the compressor as well and still getting this error only when I connect the compressor to inverter converter module, what is the best way to diagnose this issue?
Thanks in advance
Thank you for an intelligent yet easy to follow video Professor! My question for you is that Toyota's current policy is that the gearbox oil should never be changed during the lifetime of the car. What is your opinion of that policy and would you recommend that the gearbox is serviced with an oil change?
Hi, if you read the maintenance schedule you will find that there is a service interval for the transmission fluid, but it varies with how the vehicle is driven. The ones I have read have it being changed at anywhere from 90k-130k miles on cars, and as low as 50k miles on trucks. Lifetime is a relative term, it does not mean as long as you can keep the vehicle running, it is a sales term to make people feel good in thinking that it never needs to be serviced. Of course, if the transmission ever leaks or malfunctions, the fluid will probably need to changed as part of the diagnostic work. I hope that helps.
I have a 2011, but I think it's labeled a gen 2. Has no screen and no auto headlights.
Which instructions should I read before working on it?
Can a prius 3rd gem hybrid be converted to a plugin? Thanks for taking my question.
thankyou Mr Kelly just a question about relative compression on a prius not using a techstream scanner being there is no conventional starter. I'm wondering if there is a way to get the MG motor to crank the ICE cutting off fuel and putting FIRSTLOOK sensor in tail pipe and looking at waveform on scope? thanks again happy new year
Thank you! I am not aware of another way to force the engine to start other than the Toyota Techstream software and scan tool. Best wishes.
@@WeberAuto I thought there was a series of steps that you perform to make the motor run, It is not recommended to drive with it. (prius maintenance mode) as follows: Prius Maintenance Mode
Toyota Prius Gen II I4 1.5L Hybrid Synergy Drive into maintenance mode. Second generation Prius model years are 2004, 2005, 2006, 2007, 2008 & 2009. To activate Inspection Mode on the Prius, the following steps must be completed within 60 seconds:
1. Keep your foot off the brake pedal. Then "power up" the car by pressing the POWER button twice.
2. Next, floor the gas pedal and fully release it twice.
3. Depress the brake pedal and keep it depressed with your left foot for the rest of this procedure.
4. Shift into Neutral, then floor the gas pedal and fully release it twice.
5. Shift back into Park, then floor the gas pedal and fully release it twice.
6. Now the HV warning light on the multi-information display (TV-like screen) should flash. This warning light has the silhouette of a car with an exclamation point (!) on it.
7. Push the POWER button. The engine should start and continue idling at about 1000 rpm.
8. Press the POWER button one more time to shut off the engine.
This last step also deactivates Inspection Mode. The important thing to remember here: Never, ever road-test a Prius while it's still in Inspection Mode!
Dear Professor Kelly, thank you very much for this very informative insight to the Prius Gen3 Transaxle. As far as i understood from it, the transaxle fluid (oil) does absolutely not come in contact with the stators and motors of this transmission? I'm asking this because in some forums people state that the transmission fluid need to have some dielectric (isolating) properties to make sure that the windings of the stators and motors are not getting shorted. This always seemed nonsense to me. Am i right?
Thank you! The stators are cooled by the transmission fluid running over them. The stator windings are insulated and will not be shorted by the fluid. The rotors are just magnets in a laminated case. I hope that helps
Thank you!
hello Mr kelly I really enjoy your videos and have watched them many times as I have taken a few of these trans apart. What I am seeing as far as trans fluid is it seems to not be pumped into the stator area and confined to the differential/planetary gear box as lubricant. Looks to me like only inverter fluid is routed around the outside of the stators in sealed channels and that is used as stator coolant not the trans fluid. Please correct me if I am wrong. And thank you very much for taking the time to do these tutorials.
Thank you! That is true for the 1st and 2nd generation transaxles, but the 3rd and later models also have sling lubrication with oil catch tanks that direct gravity fed fluid to the bearings, gears, and both stator windings (for additional cooling).
could you be thinking of the ac comp.
Can you tell me what are the dimensions(inner and outer diameter)of the counter driven gear bearings, i belive one of them is worn because my car makes a noise while i drive and i have checked it is not a wheel bearing noise.
Is there room in the trans-axle to reverse the drive direction of the forward gears at the final? such as installing this unit in a rear wheel drive vehicle which the tires sit in front of the engine?
No, it is accomplished by the difference in the MG1 speed verses the ICE speed. Thanks for watching
@@WeberAuto I'm not sure my question was understood, as an example - in many differentials there's room to flip the ring gear and carrier 180 side to side and reverse the final output.
@@gehidore No. If MG1 spins faster than the ICE, underdrive gear is obtained. If MG1 spins slower than the ICE, overdrive gear is obtained. If MG1 spins the same speed as the ICE, direct drive gear is obtained.
@@WeberAuto I give up on this question as I'm probably not presenting it in a comprehensible way.
At cruising speed, low engine rpm, mg1 have to reverse rotation to achieve low engine rpm. What makes mg1 to rotate in reverse? Is it powered by the high voltage battery or mg2 providing electric power to mg1? Thanks.
Around time frame 24:17 to 24:30 you stated that all the torque from the ICE is transferred to the ring gear when Wice = Wmg1, but actually this is not true. It's a subtle point, but an important one.
If Wmg1 (angular velocity of MG1 in rad/s) = Wice and both are > 0 rad/s, then Wice = Wring = Wmg1. Now let's say T (torque) of ICE is 397NM. This comes from P/W=T or 50.022KW/126rad/s = 397NM. So the total torque is 397NM (ice) = Tmg1 + Tring, Now Tmg1 = Tice/(1+p) where p = Nr/Ns or 78/30 = 2.6. So Tmg1 = 110.278NM and so this leaves 397NM-110.278NM or 286.722NM going to the ring gear. As you can see ICE's torque (397NM) doesn't all go to the ring gear. Thanks.
Thank you
The video and the explanation are fantastic. One question: Can You tell me the number of teeth for the final gear and the counter gear?
Thank you, yes, 24:77 on the final drive and 54:55 on the counter drive gear
If electric power from the Ni Metal hydride battering is use to make MG1 spin at the same speed as the IC engine, maximum torque from the engine is applied to the drive shaft and the wheels (because the planetary gear set, the sun, planets, and ring, all turn as one). I'm not clear about what happens when MG 1 is spinning at a DIFFERENT speed than the speed of the IC engine - about what happens if electric power from the Ni metal hydride battery to MG1 makes MG1 spin Slower than the IC engine. And is it correct to assume that MG1 cannot spin Faster than the IC engine? So if MG1 spins at the same speed as the engine, maximum torque from the engine is applied to the drive shaft and the wheels. If MG1 spins slower than the engine is less torque applied to the wheels from the engine? What about if the engine is turning but MG1 is not turning? I'm thinking that MG1 does not actually supply torque to the wheels, it is used as a generator to charge the Nickel Metal hydride battery, and as a motor to start the IC engine and I'm thinking MG2 is the only one of the two MG devices that supplies torque to the wheels. Is that correct? I'm getting confused. I saw the engine being turned (actually the flywheel being turned), MG1 was locked up to the engine, they were spinning together, and yet the drive shaft not moving. So it is not always true that if MG1 is spinning at the same speed as the engine, that the engine is supplying torque to the drive wheels.
If the drain and fill is 3.9 quarts, then what is the total fluid capacity of the system?
dear prof Kelly thanks for videos
my question how many poles of permanent magnets in mg2. and mg1
8 Poles each
Good talk..thx
Hi I just replaced 3Gn engine and I’m having problem to drive ones I put the car on drive won’t go I just replaced the engine that’s all plus I did drain the fluid from the transmission and bought brand new fluid from Toyota dealership that is recommended for Toyota Prius and I put it in there and I can drive the vehicle at all any help please plus some people saying that I have to mark the flywheel to certain position before i put the clutch plate thanks
Hi, You do not have to mark the flywheel, but the torque limiting clutch disk does have an engine side and a transmission side. I recommend checking for trouble codes. Make sure the electronic parking pawl motor is connected to the wire harness as well. Maybe it is stuck in Park. Best wishes.
Can the MG1 and MG2 motors be mounted outside the transmission to make them easier to replace?
It really should never be any reason for them to fail. The motors cannot be mounted externally because they are lubricated by a oil bath inside the casing, as well as temperature controlled.
Hi doctor is the transnission different between the Toyota prius plug in and this
No, they are the same
So strange that the ICE always starts when speed is over 43 MPH even when no power is needed, like when going down a hill and accelerating due to gravity.
Is there a way to “lock” the differential?
About Engine reduction gear perfectly called that gear
Thank you
Thank you doing all the nice videos
Lexus brags with the fact that the CT200h has a sport mode with features like 650 Volts hybrid system for better acceleration and mid-range response. I know that they use 500 Volts for the Prius. Can you please explain the quirks of that car?
Hi, the third generation Prius 2010-2015 and the Lexus CT200h 2011-2017 both use the same P410 transaxle, engine, battery, inverter converter, and system voltages (650V). The 2nd generation Prius used 500V. The sport mode is nothing more than a throttle response variation making it seem like it has more power. The CT200h is 45-90kg (100-200 lbs) heavier then the Prius depending upon the vehicle option package. I hope that helps.
connectorxp .
Hi Sir again I'm RAMZI . please can you tell me again how can i find pin 1 and pin 3 on INVERTER HYBRID TOYOTA GEN4 P610 ON Inverter its 2 connecters one (24pin ) another connector (13 pin )
pleas if you tel me hwo can I connect power 12 volt to run InverterI will be very grateful to you
Does the rotor mg1/mg2 rotate in oil or not
perchè ha 2 meccanismi epicicloidali invece di 1 soltanto?
Sir what is the maximum torque that MG1 provide as a motor ?
That specification is not published, MG1 is not used as a motor to help propel the vehicle except in the 2017 and above Prius Prime with the P610
@@WeberAuto Hi. Im using an android app called hybrid assistant that it is connected to the hybrid system via an OBD device. In highway speeds of around 60 mph the MG2 becomes a generator and the MG1 provides traction in cooperation with the ICE. The MG2 rpm was 7700, ICE was 1430 rpm and MG1 was at 2480 rpm.
MG2 was generating 8.2 kw of power, ICE 13 kw and MG1 6.4 kw of which 1.7 kw was coming from the battery.
Hello, What is the rpm of single MG2 for 3-nd generation Prius?
12,000 RPM
@@WeberAuto Thank you! Is the rpm of single MG2 for 2-nd generation Prius 1200-1450rpm?
@@DGach1972 No, it has the same maximum RPM rating as MG1
Which Transaxle will be in my 2017 Lexus CT200 please?
P410
What transaxle does the Lexus CT use?
what's best oil or additive
So p410 transaxle got filter master
my brain hurts
So did mine the first time I tried to figure it out
I never owned anything other than Toyota for long term car. All other cars i flip it for profits.....
Very well explained.
Thank you
thank you
what is the main difference between prus 4rt gen and the prius prime?
The final drive gear ratio and an external electric trans fluid pump
@@WeberAuto Thank you so much sir. I love your channel so much!
@@WeberAuto Prof. Kelly, Do the stators are exposed/submerged in the ATF? I am wondering if it is cooled by ATF because it has much less problems than Gen2 Prius on the burned stators.