Cruze transmission limp mode… No communication with TCM…U0101 code due to prior history repair
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- เผยแพร่เมื่อ 27 ธ.ค. 2022
- 2014 Chevy Cruze customer states multiple warning lamps and messages. ECM code U0101 set and TCM will not communicate diagnostic video.
Service power steering
Service stabilittak
Service traction control
All related to no comm. with Transmission control module.
Found underhood fuse block terminal 37 of connector X3 bent, appears to be related to a repair someone has performed in the past.
Resolved without any parts being replaced.
#mechanic #cars #broken #professional
Excellent video, I am now a subscriber, my brother bought a 2015 Chev Malibu 9 months ago, it never worked properly, it wouldn't shift, no gear shift indicators on the dash, doors locking, unlocking and the horn and wipers stopped working. We did some troubleshooting numerous times without proper wiring diagrams. After watching this video, we pulled the pin connector off the TCM, we had no voltage on the pin that you said was a hard positive, the ground pin was good, we removed the cover from the pin connector, after it was removed from the TCM, we could see a spot of corrosion on the red/green wire, at this point we didn't know whether it was broken under the corrosion, we then pulled the fuse box and did a continuity test on the wire from #37 on the plug under the fuse box (red/green) and the pin on the TCM connector, no continuity, we then scrapped off the corrosion on the spot on the red/green wire and it was broke through, we were lucky enough to have enough wire to splice a short piece onto it, we now had continuity on the red green wire from pin 37 to the TCM connector, put it all back together, the wipers and horn were working, took the car for a test drive, it was shifting properly, no service engine light and we had our shift indicators back, thanks very much, you're the best. 😀
Hell yeah! Glad you fixed it, good find.
Thank you very much!
Where is this connector?
Ok i found the connector and it does have power at the connector and at the fuse box. Would the power steering be affected as well cause it says service power steering. The steering still works but its a little more hard to turn
Thanks you gave me hope! When the lights come on in the sky da Morrow I will check on mine. You're awesome!!!
I do what I can. Thank you!
Update with what you find.
I have this same year, make, model, and problem which occurred a couple of days ago after recent cold spell in Atlanta. Have the same code u0101, and all other symptoms, although no one's ever worked on the wiring as far as I know since I purchased it at 53K miles. Currently at 134K miles. Thanks for the video as it's very timely for me.
Hopefully something in this video helps. Feel free to comment further questions regarding diagnosing your car.
Thank you for commenting Derek.
Sorry for bringing up an old comment but did you ever figure out what it was? Just got a cold spell and got the exact code and problems as well
@@pablodelarosa4201 I wound up having to replace the TCM inside the transmission to correct this.
@@pablodelarosa4201 I wound up having to replace the TCM in order to solve the issue. It cost me roughly $1,800 (I believe) to do so, parts and labor.
@@DerekCaffe Thanks for the reply! I'm hoping it's more like the video cause that means it'll be less money lol but we'll see. its at the shop now
Thanks for posting. This is the closest thing I’ve found on the internet to the issue I have. My car could run fine for 100km, then do this crazy possessed thing with the gearbox going in and out of gear, hard thumping and the door locks shooting up and down. Also the ESC light on and it gets the code 0101 TCM communications. I’m checking index my fuse block tonight
Sounds like you have an intermittent network drop out.
If it’s good most of the time and only faulted sometimes it means most likely the fault is a loose connection or wiring short somewhere.
Thank you.
Finally someone that has had the same problem as me lol... I'm going thru this now
please what did you find out and what did you do to fix the problem
@@christinebaker8649 it was likely the TCM was very sensitive to low voltage (under 12.0 ) which explains why the previous mechanics first went with a new battery and alternator. The fix for me after eliminating all other possibilities was a gearbox replacement. TCM is integral to the box. Been a few months since replacing with a second hand box and it’s been fine.
@AlsETypeResto thank you so much we'll try that. I've never gotten the code u0101 until today... I've always gotten thermostat and electrical connector.. changed them both and still nothing but I'll definitely try this thanks
My 1st sub thanks for the upload
Thank you very much!
Good job!
Thank you very much Richard!
Thanks for commenting!
great job!
Thank you very much!
I can’t get the connector to the TCM to come off. You made it look like it comes off easy
There is a red CPA clip to remove first, and then sometimes those cam lock connectors get badly stuck due to dirt.
In that case wiggle and rock while you carefully move the cam lever open and closed, do not use the lever to force the connector, use your hand to assist the connector.
Thanks.
What’s crazy is I have a transmission shop doing the TCM right now. They actually replaced the entire transmission, but they called me telling me that it’s still not communicating with my vehicle. Sooo at a lose rightnow
@DadsGarageDiagnosticSpecialist Great Video! My wife has a 2014 Holden Cruze (same as the Chevy Cruze) and our mechanic has told us the TCM is faulty and needs replacing. We have the same error code U0101. Prior to sending it to the mechanic i found error code 136 displayed on the dash and when i put my OBD2 scan tool on i get code U0101, no communication to TCM. I have checked all fuses & they all light up. I fear my mechanic wont check any wires or electrical components & simply diagnose the car with a faulty TCM without proper diagnosis as per your video. My mechanic has used there scan tool & found no communication with the TCM, checked fuses & thats it! Do you have any suggestions for me going forward? Where did you get your probe test lights from? My local automotive store only has the one size test light which i used to test my fuses. Any help is appreciated we have lost alot of money 😢😢
The circuit testing to verify a faulty TCM is fairly easy and doesn’t require any fancy tools so they don’t have any excuse if they’re not testing the wiring which is a must. After it’s verified that the TCM needs to be replaced it must also be programmed afterwards. Thank you for commenting.
Edit: that test light should also work just fine for most uses. In some cases the cheap-o light is more desirable as it may place more load on the wires for a better test.
Follow the test process in this video and also in this video to prove a faulty TCM or faulty wiring: th-cam.com/video/QuLlP25zP_8/w-d-xo.html
i had to re-pin my connector on my 16 impala, TCM was fine. i wiggled it while the car was running one day and the engine smoothed out and stabilitrac light went off
That is fairly common. That’s one of the first things I check.
Thanks for sharing.
Same lights I had in my car but it was the power steering! But my code was U0131!
I have a video for that code too. Check it out: th-cam.com/video/qjylq8C0aFU/w-d-xo.html
Thanks.
I have a 2015 Impala 3.6 LFX and I had a U0101 code which put the car into limp mode, no gear selection showing, stabilitrak light coming on every fuse days. I checked wiring, continuity, and everything was fine.
These last gen Impalas have problem with condensation getting into the inside of the fuse box for some reason. Try taking the whole engine compartment fuse box apart to clean the prongs underneath. For my 3.6, there are 3 10mm bolts that go to 3 individual pieces that come out from the bottom. The bolts do not come all the way out.
Then on the two longer sides, 3 clips you have to separate with a flathead, and I think 1 on each shorter side. Then it comes out. Clean with dielectric parts cleaner with a cotton swab. Also note I did not see any condensation inside of the fuse box. But for me it worked for 3 months
The same thing happened again. Then I took the alternator out, had it tested and it failed. Also took the throttle body off so I could clean it. Mine made a bad rattling sound when I went to shake it. There's gears inside of it that may move around when shaking. I never had a engine light for the throttle body so I left it on. Even went to LKQ and those made the same noise but less aggressive than mine. After that the problem was fixed. I got a stabilitrak light that would come on every 3 days almost and it has not came back for 3 weeks now
If the light comes back, I may replace the whole throttle body. The first time I even replaced the TCM but that worked for a day
Good info. Thank you for commenting!
I have not been seeing too many fuse block failures, but yes it does happen.
If your problem returns you may want to test for any loose terminals in the connectors.
I'm having the same exact issue in my 2015 Impala ltz. I replaced the TCM and it worked for 2 weeks then went back to limp mode. Replaced TCM again with warranty and it now has no communication with TCM so I can't code the thing. I've had this problem for going on 10months with no solution from 2 dealerships and 4 mechanics. Idk what else to do at this point. Can u help please
You need to find somebody capable of diagnosing a no communication fault. It should be fairly easy to determine why the TCM will not communicate. Thanks.
@@justinreed9821you ever find out?
@@justinreed9821 did you ever find out what was wrong? I have a 2014 impala and I've been dealing with the same issue and it's really annoying. Every mechanic I've been too acts like they don't even want to touch it.
I’m going through the same thing with my 2014 Buick Verano, took it to the dealership and they couldn’t fix it. Was this car’s problem intermittent or consistent? My car sometimes works fine and then sometimes it gives me those codes. The problems has been happening more frequently tho…
Yes this failure was intermittent for a while until it ended up staying in the failed state long enough to be accurately diagnosed.
Malibu 2015 v4 code u0101 ? i fell the gear not change smooth and The gas pedal does not respond quickly
Diagnose the U0101. If it isn't shifting right I wouldn't drive it otherwise you risk overheating the transmission.
Thanks.
Will getting my TCM replaced fix this problem? Im not having issues with switching gears, but my engine light turns on and off, and the same lights turn on for a second then right back. Off… I also experienced the shaking, limp mode, and doors locking/unlocking.
Usually if the problem comes and goes, it is not going to be the TCM. More likely to be wiring or loose connections. Maybe even a loose ground.
Thanks.
@@DadsGarageDiagnosticSpecialist why are they trying remove the whole body valve?
@yungbevvo the TCM is mounted on the valve body.
Do you have to disconnect the battery before removing that fuse box from the connectors? Or is it ok to leave the battery connected?
It’s a good idea to disconnect the battery yes. I had the battery connected for testing.
Thanks.
2016 Chevy Cruze limited LT runs well but seems to start in a high gear and/or never shifts. Manual mode not operating. Only code is for turbocharger / supercharger bypass valve mechanical. Local mechanic said the bypass valve malfunctioning could cause the transmission not to shift properly. In my opinion the systems have nothing to do with each other. Am I wrong? Car also seems to be making a noise similar to a wheel bearing but seems to be coming from transmission.
Need to know what codes you have. By your description there should be some sort of transmission code or some other code setting. If no codes and the transmission is not shifting at all it may have some serious problems inside.
Does it lack power related to the turbocharger maybe and the transmission is working ok?
Thank you.
@@DadsGarageDiagnosticSpecialist currently only code shown is p2261. It is possible the lack of power could be turbo related. I will try a better scan tool and see if it shows any trans related codes thanks for the tip.
P2261 sets when the turbo bypass valve has a problem yes and that would cause a lack of power if it were stuck open.
I'd be concerned about whatever that noise is too....whether it be related to a turbo problem or possibly the transmission. The manual shifting should still be working and the transmission should still shift, but it might refuse to shift into the next gear if the engine is so severely lacking in power that it can't. Thank you.
Also check out my recently uploaded video on a 2016 Cruze with a faulty turbocharger: th-cam.com/video/4sCKjBiLyv8/w-d-xo.html
@@DadsGarageDiagnosticSpecialist yeah that is all pretty much what I was thinking. I'll start by diagnosing the turbo issue. And move on to the transmission next. Are Chevy Cruz's known for clogging catalytic converters at 127,000 mi?
@@matthewglaze5398 not usually the catalyst shouldn’t fail unless there was something catastrophic that caused it to fail.
I had this 0101 code recently. I wiggled the TCM connector where it plugs into the transmission and the problem went away..... Check engine light isn't coming back on. Is there a simple way to replace this connector as 1 part? I don't want the issue to return.
The connector is available as a whole new piece including the wires and splices. Grab one from the dealer or get the part number from them and order it online….would highly recommend only buying the OEM AC Delco rather than aftermarket.
Thanks.
How do you remove that cable that you blew with air it seems impossible to remove??
Wiggle and pull while you move the lock lever. Don’t use the lever to force the connector, it will break.
Sometimes you may need to blow air from the outside and also spray some WD40 to help get the connector loose.
Thanks.
@@DadsGarageDiagnosticSpecialist thank you I was able to remove it
Great Video, Great Communicating with your subs and/or viewers and I am a New Sub..
I can really use a second opinion oh what's going on with my 2010 Impala 3.5L with 64K Miles. Second Owner and Uncle was First.. I know its long but Here's what's Going On.
12-22-22 - New Battery Due to Repeated Jump Starts
03-21-23 - P0411 (See Below), P0522/P0523 (Engine Oil Press Sensor Circuit Low/High Voltage). Dealer Replaced Sensor
04-10-23 - P0411 (Secondary Air Inj System Incorrect Flow) Self Installed New Check Valve and Fine.
06-25-23 - P2440 (Secondary Air Inj System shutoff valve stuck open. Limp Mode, Warning Chimes, and Service Stabilitrac/Traction Control Warmings.
06-27-23 - P2135 (Throttle Position sensor 1-2 correlation) Limp Mode, Chimes, and Service Stabilitrac/Traction Control Warnings.
07-01-23 - Nothing Done since 06-27-23. Before starting, Scanned, No Codes. Started fine but check Engine Light. Scanned and No Codes. Cleared Codes and Drove perfect.
08-24-23 - No Crank No Start. Jumped it and was fine. Brought it to a SEMI Local (30 MIns) Mechanic from a Good Friend Referral.
08-29-23 - Determined 8 month old battery Failed. New Battery and New Secondary Air Inj Pump (Was Working BUt VERY Loud).
12-15-23 - Tried Factory Remote Start. Went out and wasn't running. Started it but Running Rough (Maybe Limp Mode). All the above warnings and chimes plus all the gauges were freaking out. Turned off and Tried again same thing. Left it for a day or two, No Crank No Start. Tried it again and as I was bringing the key back from the Run Start Position it Cranked For a Split Second. Tried several more times No Crank No Start.
12-20-23 - Put in On Position and Hooked up former Mechanic Scanner and "Communication with Vehicle has Been Lost". So couldn’t scan any codes or check any DATA… I tried Starting and same issue as above.. Tried to Swap the Starter relay with a duplicate Rear Defog Relay and it started but the gauges were still going crazy, chimes, Warning Messages and running ruff.. I tried Hooking the Scanner up again and the car began to idle fine, no chimes or messages but all the gauges showed as 0 and you could not see what gear it was in… Tried to scan and "Communication with Vehicle has Been Lost"
12-22-23 - We decided to take it to the dealer for diagnosis. Went to bring to dealer and no crank no start. Messed with the battery connections , grounds, fuses, relays, connectors and it started up perfect. No check engine, lights, chimes, and idled perfect. Turned off to get my wallet to take for ride. Went back out 5 mins later and no crank no start. Finally got it started and drove to dealer . 1/2 the trip the door locks kept locking and unlocking constantly (This was NEW), gauges went crazy, Chimes and warning messages… But the Car was not in Limp Mode… Second half the car went into limp mode and no chimes no gauges no locks no nothing and could only go 20 mph. Nerve racking. I got there and they went to bring it in and no crank no start. Got it Started, Drove it in, hooked up scanner and "No Communication". The first thing they did was put a new negative cable Connector on it and it cleared up all the chimes, gauge wackiness and warning messages. Tuesday they are going to concentrate on the starter..
12-26-23 - Dealer Replaced the Starter.
12-27-23 - Started but that same weird Crank after I started Coming Back from the Start Position.. Drove Perfect.
12-28-23 - Started and Drove Fine.
12-29-23 - No Crank No Start. Made appt for 01-02-24 with dealer to fix.
12-31-23 - No Start No Crank.
01-01-24 - Using Mult Meter I check the Battery and it read 12.2 V… I visually inspected the Fuses, Tugged and Inspected any Wires that Had Tape on them, Tugged on Connectors… I tested the DLR Pins 6 and 14 and got 60 ohms… I turned the Key to ON and hooked up Scanner and No Communication… Got Mad and Just tried to Start it and It Started… Beings I didn’t Initially try to Start it, I am not sure all the Poking and Prying did anything or it was Just ready to Start.. The Car Idled Great and No Issues Except the Check Engine Light was On… So I scanned it and got the following (9)Codes: U0073 (Control Module Comm. Bus Off) (2) Stored, (2) Pending and (2) Permanent, P0700 (TCM Requested MIL (Check Engine Light) Illumination) Stored and Pending & P150C (TCM Engine Speed Request Circuit) Pending… I Drove it to the Dealer with the Scanner Hooked up (Because of what happened on 12-20-23) but this time it was Not In Limp Mode but it didn’t have full Power.. The Gear Shifting was VERY HARD where you Could Here and Feel each Shift.. Just before I pulled into lot I Cleared the Codes.. I pulled into lot and disconnected the scanner and drove it around the lot and now I did not here or feal it going into second gear.
They have had the Car Since and they say They Have not had the No Crank No Start issue but they did get the SLuggish drive (Not Limp Mode) and had the warnings and Chimes.
BUt by the time they get back and start Diagnosing the Car is fine again. They think its a Bad PCM and that they don't think it's Wiring Issues.
If you have read this Far I am Thank Full for your time... Any help or thoughts would be much Appreciated... This is my Sons car who just got his license last year and the car doesn't get driven hardly at all.. He is afraid to drive it and Frankly I don't blame him.. Just Me doing local errands and to work once a week..
Sincerely Dan
Thank you very much! I do what I can.
That particular era of impala had a lot of body control module failures, which could possibly cause all of those weird problems.
Also, you may have something loose in or near the under hood fuse, panel it sounds like… Or possibly a battery cable loose or corroded. It would also be worth checking the battery positive cable for being loose at the starter motor.
Measuring resistance at six and 14 if you are measuring 60 ohms during the fault… That means the network circuitry is at least intact
.
Get an auto electrician to clone a good second hand engine ecu.
So I have this exact same issue. Troubleshooting next steps lead me to this video (VERY helpful). I disconnected the connector to the TCM, and checked PINS 1 and PIN 2, and ignition is all fine. How would I check the data?
Year make and model? Kind of depends what kind of tool and testing method you’re using. You said you have positive current, what you actually mean to say is you have positive voltage.
Voltage=pressure
Current= rate of flow
If you are measuring more than 0 volts on terminal 2 which should be the ground, this implies the ground is open or high resistance. I’d recommend using a test lamp.
Thank you for the comment. Let me know if I can further assist.
@DadsGarage Diagnostic Specialist it's a 2014 Chevy Cruze LS just like the one you worked on. I checked the B+, and both + wires from ignition using test lamp. The only thing I dont know how to test is to see if it's sending data from the TCM.
@@ANN4ISME the only tool I truly trust for testing a data communication circuit is a lab scope so you can view the signal quality. However most of my career had been spent working without the right tools and “make it work”. So here’s what I would do to verify a data circuit.
1. You need to prove the module has everything it needs to operate, that’s easy because it only needs a few things such as constant battery positive voltage, ignition voltage or wake up signal, ground at all times.
2. After proving that, if you want to test the integrity of the data comm circuit you need to ask some questions? How many modules are failing to communicate? If only the TCM is failing to communicate then most likely the problem is related to only the TCM circuits, as some no communication faults can be elsewhere in totally unrelated systems which I show in another one of my videos.
Disconnect both ends of the circuit with the battery disconnected and use a DVOM to test
A. Resistance end to end which should be 0 ohms - 10 ohms
B. Resistance to ground which should be infinite or OL
C. Resistance to battery positive which should also be infinite or OL.
If the power and grounds are ok, the data comm circuit is ok, and all of the other modules and ok and also setting codes which relate to “I can’t talk to the TCM”, then we have to assume the TCM is faulty.
Module failures are rare in my experience except certain makes and models which have high failure rates with no associated cause. In most cases if you find a module has failed you need to look really close at why the module failed before you plug in the expensive new module and destroy it.
I have the same vehicle 2014 Chev Cruz 1.4L.
Power, ground, & Ignition pins are all ok on in that TCM connector. I still get U101 . As you mentioned I also have BCM no communication as well where TCM gets it is feed
Hi friends, mine it'a Cruze LS 2010 2L z20s1-D 92kw with manual transmision, i had U0101-71 dtc on EBCM - lost comunication with TCM, how is that posible if manual transmision ?
I have a 2012 Chevy Cruze with code p0700 and the car jerks when changing it to reverse, and it seems to not have enough power to go up my driveway. Not to sure what’s the problem
Sounds like it is going to need a diagnosis...the transmission is most likely in limp mode.
Thanks.
I’m also getting codes p026F does this mean the tcm is bad?
P062F sorry**
P062F is an internal module fault code...depending on what module is setting the code and what symptom byte is set along with the code will depend whether the module needs to be replaced or just needs to be programmed.
Is it a new TCM or valve body? If so, it needs to be programmed.
Where are you located? This the same problem I’m having with mines
I am in Oregon. Thanks for commenting.
Holy crap always check them bolts 8:30 found loose once whole vehicle freak out
Yep! I’ve seen that a few times.
Thanks.
2016 Chevy Cruz LS 1.8 automatic I have it at the shop right now and they’re currently trying to figure out what the issue is with my vehicle putting another transmission and it’s still not communicating with my vehicle 😢
Sound like it has a blown fuse or a wiring fault somewhere. The transmission must be programmed to the vehicle when it is replaced also.
Find a different shop.
Thanks.
@@DadsGarageDiagnosticSpecialist that’s pretty much what the guy was telling me. He said the transmission passed all the test. I’m not a mechanic so I’m not sure what that means but what he said was now let us hooked up to the car. The computer won’t see the TCM or anything, but he said he’s gonna continue to work on it and give me an update. I just hope he’s able to figure it out and I don’t have to spend money with him to go to someone else to spend more . Thanks a bunch
I have a 2014 Chevy Malibu that had this same U0101 code. Goes in limp mode and is stuck in 3rd gear. According to Chevy dealership, the TCM is inside the transmission, therefore it is an internal issue and they are recommending to get a new transmission…. I replaced the gray colored relay fuse and that didn’t help initially, but now my my car is acting normal. Shifts fine, check engine light went away, but I’m afraid its gonna lose communication with the TCM again.
If the transmission acts normally then it probably doesn’t need to be replaced, maybe service the fluid to check the health of it first. I’d suggest a re-diagnosis.
If the problem comes and goes, it is almost certainly wiring related… It could be a faulty TCM failing when warm, but I don’t see that almost never….. if so the TCM can easily be replaced by removing the transmission side cover.
Thanks.
My chevrolet cruze 2014 model was giving me anti theft check ligt, later the key could not start the car. We try replacing the key and now is giving us this error;Chevrolet Cruze no communication with ECM, TCM and BCM.
Please help us.
@seinadziwornuernest2960 needs to be diagnosed
I have the same make year and model my car is at 220k and now acting in this same manner I cleared my codes and is running good for now but how did you know to change a certain fuse and what fuse is that you mentioned located? Did the problem come back?
@@traviscarver7163 I misspoke in my original post, its not a gray colored fuse. The gray one I mistakenly mentioned is the A/C clutch relay. The fuse you're looking for is called "Transmission Control Module Battery" and you can locate it by using the diagram underneath the fuse box cover in the engine bay. The problem never went away after I changed that fuse. I am still having TCM issues with my 2014 Malibu. My car is at 193k miles. The TCM intermittently goes in and out. I have to drive my car for about 20 minutes and the TCM initializes while I'm driving and the car drives and shifts fine. But when I cut the engine off and let it sit for a long period of time, the TCM will go out again when I re-start the car and will be stuck in limp mode which is 3rd gear only...... then I have to drive for another 20 minutes before the TCM comes back. I took it to a second Chevy dealership, paid another $200+ in diagnostic fees and they told me there is some kind of electrical/connection issue and I would have to pay another $1,300 for them to further diagnose it. Obviously I declined that. I am beyond frustrated, but I am just dealing with it right now. I have disconnected the TCM harness from the TCM over and over and over again, but to no avail. The next thing I'll do is probably do is disconnect the entire engine bay fuse box and examine it, which was done in this video.
I have the same code on my impala is a 15 but it’s telling me to replace the transmission valve body assembly is this true
Yes, similar to the car in this video the transmission control module is mounted to the valve body, it may even be the same 6 speed transmission or a variant of it. The module itself can be replaced separate from the rest of the valve body.
In my experience, module failures are rare on these and usually the problem is wiring related.
Thank you for commenting.
Si retiro el arnes para probarlo con mi osciloscopio se desprograma?
Disconnecting the harness for testing will not cause a problem with loss of programming. It will be safe to perform the test.
Thank you.
I have a Chevy Impala 2013 with the same code as this and it does the same thing doesn’t show what gear the car is in and it jerks when changing it only to reverse and it’s in limp mode I believe I’m considering changing the TCM or should I look at the connections and everything before doing so ? 😭
Thank you for commenting Fabricio.
I would recommend retrieving the codes from the Transmission Control Module if possible before doing anything.
@@DadsGarageDiagnosticSpecialist thanks for replying to fast, but how would you retrieve the codes from the transmission control module ? Do you need a specific scanner ?? My brother only has an obd2 scanner that’s how we were able to read that it had the U0101 code
@@fabriciodiaz1018 yes sometimes you need a more advanced scan tool capable of communicating with non-powertrain related modules.
A generic OBD2 scan tool can usually communicate with the ECM and also the TCM. I’m going to assume you retrieved the U0101 code from the ECM indicating that the ECM is unable to communicate with the TCM. If your scanner is capable of checking TCM codes and data I would use it to attempt to read code/data and if it fails, that confirms the lack of communication.
Communication diagnostics can have multiple failure scenarios, but if it’s only the TCM failing to communicate which is shown in my video….that means the problem is with the TCM only…..so that means we need to check TCM power and ground supply and then check the communication circuits. Watch the video again where I explain on the wiring schematic there are only a few circuits to check. It could be as simple as a blown fuse.
Let me know if you need more assistance. Thanks.
@@DadsGarageDiagnosticSpecialist thank you so much I will let you know!
@@fabriciodiaz1018 excellent. I’ll assist as much as I am able.
I’m having the same exact issue except it drives as it usually does but it’s hard to pick up a speed. Once I put up a speed I have to maintain that speed, I have to really press on the gas to go. Went to AutoZone code U0101 came up nobody seems to know what’s the issue or how to fix it. Everyone just keeps saying lost communication with transmission control module. Any advice?? I have a 2014 Chevy Cruze LTZ
If you follow the general steps of the video you’ll may be able to figure it out.
Firstly you’d need a scanner capable of communication with the TCM, and you’d have to verify that the TCM is failing to communicate with the vehicle modules and also the scan tool. After confirming the failure to communicate you’d need to consult the wiring diagram and test the TCM circuits as shown in my video to determine if it’s a wiring problem or a faulty control module. It’s usually NOT the module.
Thank you for commenting.
@@DadsGarageDiagnosticSpecialist where did you purchase the scanner from that you have in this video?
@@biancatiana2228 mine is a factory scan tool from the dealership. Testing can be done with other aftermarket scan tools also.
If you are going to invest the money in the scan tool and use it once, it may be a better idea to pay for a diagnosis.
Thank you.
@@DadsGarageDiagnosticSpecialist ok thank you so much!
You’re welcome
Same issues and the door locks are engaging, disengaging.
What kind of car? Is the transmission in limp mode also? Thank you.
I have the same thing. Door locks crazy up and down, TCM com code, in and out of gear and hard thump when engaging.
Same exact problem im having@@AlsETypeResto
Hello DadsGarage, I have the same problem on my 2011 Cruze but the code that appears is P0700; The strange thing is that, if I delete the code it works for 1 or 2 weeks and then the problem returns, what could it be? Do you think it could be a false contact or something related to the solenoids?
P0700 indicates that there is a trouble code stored in the transmission system so you need to read the codes from the transmission also.
Thank you.
@@DadsGarageDiagnosticSpecialistThanks for help, is there a special scanner to read transmission codes? I just only have a bluetooh device connect to my android phone and why do you believe that when i clean the code the car work fine 1 or 2 weeks in a raw? :(
@@Sabs761010 some generic scan tools are able to read transmission codes, but usually you do need a professional grade scan tool and the applicable manufacturer communication access to diagnose these.
If the code is taking a while to code back it might mean there is only a fault sometimes. We should find out what the code is and then go from there.
Thanks.
@@Sabs761010I know it's late and I don't know if you fixed it already but the issue that is common on these cars is that transmission fluid gets into the connector and causes an intermittent connection or a complete loss of connection on that body style Cruise.
I’m having the same issue with the same code my car jerks in reverse the car doesn’t go over 40 mph should I check the fuse box ? It’s been coded by a mechanic and the problem is the TCM
Yes if you follow the general direction in this video you should be able to find it.
Year make and model? Thanks.
@@DadsGarageDiagnosticSpecialist Chevy Cruze 2016
@@DadsGarageDiagnosticSpecialist and where can I find the terminals to replace ? The car has been sitting for a while it was gave to me by my grandad I replaced the motor the car was running fine for 2 weeks that’s when it started happening with the jerk in reverse and everything else
@@sammiesosaaa could be a loose ground related to the engine replacement
@@DadsGarageDiagnosticSpecialist have any suggestions on what I should do ?
I have the same problem, I already did everything you say but it only worked for a while...
can you help me?
Year make and model? What codes and symptoms do you have?
@@DadsGarageDiagnosticSpecialisthave 11 Chevy Cruze I changed the pcm and solenoid and now no crank. Have trouble with key fob and scanner keeps saying no contact to ecm
If the engine control module was replaced an immobilizer system learn must be done.
Thank you for the video. as it's very helpful for me. What type of diagnostic machine are you using? I have an OBD scanner. My car has error code U0101. The mechanic diagnosed a TCM problem and have them fix things that might cause the problem before fixing the TCM such as flushing the transmission fluid, changing spark plugs, and connector, and checking electrical wiring. The engine light is on and off. There are days it's off and days on with Code U0101. Spent almost $4k now going back and forth to the car shop. The Mechanic says it's transmission and will cost almost $3k for parts and labor with the used transmission but cannot guarantee it will resolve the problem. I can hear a loud clicking noise when shifting from the park to reverse gear. Shifting feels like dragging from 15-24 speed but is quiet and smooth the rest of the speed. I will appreciate any input. Is there anything else you can suggest that needs to be checked before we jumped in the direction of changing transmission? The budget is kind of tight but the car is a necessity for driving to work. Is it worth changing the transmission, especially with a rebuilt one? We are looking at bringing it to AMCO transmission. Please help.
Thank you for commenting Jessica. Maintenance services such as transmission flush, spark plugs, etc. will not cause or contribute to a U0101 loss of communication. They have have recommended a transmission flush due to related effects such as if the TCM fails to communicate the transmission will operate in default and if driven in this condition can cause transmission overheating and damage.
From your description it seems like your mechanic is just guessing, but I’m not involved so I don’t know details.
If the transmission is damaged then yes it’s advised to replace the entire unit with a rebuilt/remanufactured, but still you must solve the U0101 code beforehand or you risk destroying a new transmission.
You say some days it’s off and some days it’s on, this suggests loose terminal fitment in a connection somewhere, possibly related to the fuse panel in my video, but would require accurate diagnostics.
@@DadsGarageDiagnosticSpecialistYour response is much appreciated. We decided to just take the car to AAMCO. Hopefully, they will be able to correctly diagnose the issue. The engine light with code U0101 was gone for three days but then came back. The car is still running smoothly with no issues. Thank God. Thank you again for your video.😇
@@jeseccasantillan5195 yes of course! Thank you.
@@jeseccasantillan5195 Hey Just seeing if you got a solution to your problem sounds alot like what mine is doing
@@doyledaines9677
Hello. I am sorry for the late reply. We took our car to AAMCO transmission. They will charge $184/hour for diagnosing the problem. They cannot guarantee how many hours 2-4 hours maybe before they confirm that the issue is transmission. Now are car has an intermittent limp mode problem with engine and traction lights on. We made it home by driving 15 miles/hr. Turned off the engine when it went limp mode and the car started to jerking forward. We have it towed to a machine shop but because it stayed in our parking for three days prior to towing, the engine and traction lights went off and the machine shop could not diagnosed the problem. We asked GM motors if they can diagnosed the problem. Was told that based on the description of the problem it might be the TCM. However they cannot guarantee that it will fix the problem because there might be other problem after changing the TCM. It would cost almost $1400 or more for parts and labor. We decided to just keep the car and probably will sell it as is. It is running good so far. Ut because the car is a necessity for my husband’s job, we decided to rent a car monthly. Try to avoid encountering an intermittent limp mode issue while driving to a highway. Hope this helps.
Same car same error code...can you please sent me the wiring diagram
The video includes the wiring diagram for the transmission at 1:44 and 3:15
What diagram are you looking for?
Thanks for commenting Johann.
Will it do this same exact thing if the tcm is bad
Yes, however TCM failures are rare on these.
Thank you for commenting.
Same problem with my 14 camaro but im getting only 2 codes u0100 and p0700 also it dont happen often the problem going away and coming back.. pls help
Check the main transmission harness connector. Thanks.
@@DadsGarageDiagnosticSpecialist i will do it thank you.. it’s that serious problem or just wire issues
@@danield3566 the problem seems to be present only sometimes so most likely it is a loose connection of some sort. Could even be some transmission fluid leaking in to the connector.
@@DadsGarageDiagnosticSpecialist my car it’s in garage and there is no leaks on the floor i have the problem for 2 days now no leaks also I checked the battery voltage and it should be 13.8 myne is 12.8 and i have rust on the battery connectors i just checked now i will check the connector tomorrow thank you for replying really appreciate it!!
If that makes point
I'm having the same issue with my 2015 Chevy Impala. No one can figure out why I have no communication with my TCM. My car is stuck in limp mode. I hope this is the same answer to mine.
I have also replaced the TCM twice now and now the new one they cant be coded due to no communication with the TCM. They say there is a short somewhere but they can't find it. I've been at a loss on this car for 10 months with no solution.
You just need to find somebody that understands how to diagnose a loss of communication fault.
Thanks.
So I have taken it to another mechanic for the loss of communication with TCM and to get it coded so it will no longer be in limp mode. Once again the can't figure out what is wrong with my car. I have literally done everything but change my transmission. Im really at a loss. I've had personal mechanic look at it. I've had two different dealerships look at it. All of them with no answer.
@@justinreed9821 is the fault not present when they look at it? They shouldn’t have such a hard time diagnosing it unless it is intermittently failing.
If the problem is intermittent it is almost certainly an electrical fault.
We're looking at the battery neg still connected. And you're removing the fuse box.
And nothing bad happened.
Thanks.
Mines throwing the same, no start, doesn't know the cars in park, stuck in park.
Changed the range sensor, still nothing. Guess im checking the fuse situation next
Yes, sounds like it needs some electrical diagnosis. Thank you for commenting.
@@DadsGarageDiagnosticSpecialist its just funny, i drove it, parked it, 45 min later im having full comms failure lol. Tcm bcm ecm all fail to comm with the matco maxlite.
@@looselipssinkships6543 is the transmission control module failing to communicate with the Matco scan tool?
@@DadsGarageDiagnosticSpecialist yea, but everythings failing comms now. Like it was working then just stopped. I have 3 dif scans, the last scan it all failed
@@DadsGarageDiagnosticSpecialist almost like the vci port failed but i dont see why that would happen, i jever unplugged it, it stayed hooked up the entire time.
I'm going through same exact thing 2014 Cruze all the same dash lights
Thanks for commenting Chassidy.
There are several different failures that can result in the multiple warning lights and error messages. If you can tell me what codes you have I might be able to give you some advice.
The car in this video for example had a service power steering as well as traction control and stabilitak warnings, but no fault in any of those systems. They go into fault mode if a related system has a problem that would affect operation.
@@DadsGarageDiagnosticSpecialist same exact codes steering, traction, and stabilitrac, it's also very jerky putting in reverse. I've just went out and checked the fuses those are all good. I really wish my dad lived near me to help me out. I'm a very impatient woman and have rheumatoid arthritis so I can't imagine hunching over under my hood for long in this Arizona heat even in January it's pretty warm. So umm if I attempt to remove the fuse box as you did tomorrow, do I need to at any point disconnect battery? Oh man thanks so much for this video I've been broken down for 3 months finally just dropped the insurance because it seems to be one failure after another on this car and I've been dreading getting ripped off yet again by another mechanic. I've had to get full oil cover gasket and spark plug problem fixed twice and haven't even had it a year $1,500 each time I'm exhausted but need to try to fix it as I can't afford another one being as I gave up all my saving for this one that's been a nightmare 😩
I would not remove the fuse block at all unless some sort of test led you that direction. The reason I ended up taking the fuse block out was because I tested for power at the transmission connector and found no power, but still had a good fuse.
We need to know what codes are being set in each system. See 0:24 in the video for example. Thanks Chassidy.
@@DadsGarageDiagnosticSpecialist ok I'm gonna have to go get one of those testers in the morning
@@DadsGarageDiagnosticSpecialist & my code is U0101 lost communication with TCM
I get that code lost communication with tcm and the car doesn’t start up sometimes sometimes it starts find sometimes it hard shifts sometimes it doesn’t
Make sure the main connector on the transmission is clean and tight. Sounds like an intermittent loss of connection to the TCM.
Thanks.
0:41 16:23
I’m not sure what you are trying to say… Thank you for commenting.
What was the code? To the Chevy cruze
@@AriesRox2012 U0101 Lost Communication with Transmission Control Module
Okay
Somebody did not ask the customer the magic question: Has someone else worked on the problem previously?
with the follow up; What was found?
and the next follow up; What parts were replaced?
I say this because I find the more information you can get from the customer the easier the repair, especially when the car has recently gone through multiple shops. Meaning, one of the first tasks after confirming the problem is to check the work of the others who came before. This basic procedure can greatly reduce the time on the repair, or inform the customer of questionable non-OEM parts.
True more information is better. In my world I’m used to working with minimal information and often customers lie or don’t know… vehicle history can be very misleading sometimes.
The customer may lie, but the car never will.
I prefer to let the diagnostic process lead to the fault, it’s never let me down doing it this way starting from the basics and using the same process every time. I’ve definitely been mislead by focusing on history repairs or taking their word on repairs performed only to find later that the “new” part was faulty or something wasn’t repaired as described.
Thanks for commenting Wind Ward.
@@DadsGarageDiagnosticSpecialist I find myself asking the customer more generic questions (like are you happy with the vehicle overall? for example. which is a wide open question and not specific to the problem potentially) than necessary and sometimes they say something that they do not know the importance of, especially things or phrases other techs have told them. Usually, if you ask the right questions, there is some truth amongst the lies.
True at that point I take an extended road test with the client and have a long talk and observe the way they drive, etc.
ive been dealing with this code for too damn long, i already spent 6k on a transmission shop and they couldnt fix it and told me not to bring it back......no honor or backing in their work. so given how this cruze looks identical to my 2014 impala lt 3.6 flex fuel, im going to take apart the fuse box and see, test for continuity from the box to the connector also. it has a new TCM in it, not even 2 weeks old. the way my car is right now, i cant use it for work because it wont past inspection.
Sorry to hear that. Sounds like it needs a diagnosis.
Thanks.
Is it possible the circuit board could be bad. I get the u0101 code and trac light on when I turn my ac on. The TCM fuse is next the ac fuse and my evap im monitor stop working at that time to. The evap relay is next tcm fuse
I checked my pins. They look good
Possible yes the fuse block circuit board could fail, but I don’t see them fail very often unless they got wet or rodent infested or something.
Thanks.