Thanks for doing this video. the Cobalt that I got for our daughter for her birthday didn't run when I purchased it. I figured it would be something silly and stupid. Turns out it had three issues. There was a slight fray on the can bus wire leaving the ECU going towards the TCM. That would not allow the data port (obd2) to work. But also the ABS module was bad. While trying to find the cut in the wire that was between the TCM and ecu, I figured out that the ABS module was bad and had to do a patch a couple of clips in the ABS connector to bypass the ABS module. After I got the OBD2 scanner to now communicate with the ecu, the car was still not crank. I happen to have seen another video regarding the ground being bad in the TCM, I literally just took a instead of jumper cables and put the negative side on the TCM and the other negative side onto a ground on the body. Voila, the car started!! I was very close to feeling beaten. Luckily, I tried the jumper cable as a last resort . Thanks a lot for the video. It helped me understand the can bus better and how to diagnose it
My heartfelt appreciation to you for presenting this information in the way that you did. It is complicated but very understandable seeing that a background in electronics is so needed in the auto industry. the newer cars are even more technical, thanks
Terrific diagnosis, strange I hadn't run across this video before. IMHO and only an opinion , I generally break the system at the easiest middle point to check both directions. 2 minutes more of searching the location of all the modules and I'm sure you would have found that problem in half the time. Please understand I'm not knocking. This is a great video and great diagnosis. Not every video has to be geared to a diy guy
I like the video; I need help with my 2011 HHR. I R&R the Transmission when I had the fuse box out, I accidently shorted the main battery cable to ground now I have no crank no start. No power going to the starter solenoid. I looked at everything I can think of and can't find what I smoked.
Thanks for your input I appreciate it. I am thinking of making a more general video on the diagnostics steps that I do on nearly all the vehicles that I work on that are a no start / no crank. Also my camcorder does not work so this was shot with a nikon cool pix camera and I only had a little over 8 min of time to record.
which wires did you jump to bypass the vcim? I had 30ohms at my can bus pins not sure what would cause that. also my number 1 pin to grouns was like .5volts
I added some die electri grease to the electrical plugs to tcm, ecm,and the fuse box last Saturday 1-7-2023 and my 2008 chevy hhr never cranked again no start no crank it's driving me crazy before I added the die electric grease I didn't try to start the car. It runs great but sometimes the gauges intermittent and then it stops Trans shift hard and stop please help me
What codes are setting. I rarely add dielectric grease to connectors, I have no idea why people think that will fix something. Just makes a slimy mess l!
You did i fine... I followed right along and i pretty much knew where u were going, the first video was tough with no audio. Thanks for reposting so soon wasnt sure if u were going to or not.
I know this is an older video, but anyone else having this issue please check the UBEC connectors as well. There is a known problem with terminals being backed out/not clipped properly causing poor/no contact. 😊👍🏻
I have a crank no start where would be the best place to get wiring schematics. I checked the coil pack no spark on 1&4 crank sensor had voltage. I have replace the fuel pump, check fuses, relys, tps, pulled valve cover valve are rotating, did compression check, blew through fuel line, changed filter.Thanks in advance for any help given.
My hhr runs but my #16 pin has no power. so the obd can code tester does not communicate with the car. would you know why the#16 has no power?? Please help. Thanks.
Hello. Very good video Just a thought, if scanner showed no communication with PCM,TCM and EBCM and looking at the diagram you showed,where you can see the EBCM,TCM and PCM in that order in the circuit, wouldn't be a little quicker after knowing that one terminating resistor was not present, to isolate the system first right before the first missing module, in this case the EBCM and check both sides of the circuits at the point of separation ? With the EBCM being hard to get to, it would have pointed you straight to the VCIM . Just a thought. Thanks
I would check for codes in all the modules for starters.. you would have to have a decent aftermarket scanner to do this.. on newer vehicles like this if one module goes bad it can cause a no crank / no start
Any advise for a hot weather start problem on a 2006 HHR? Having a problem duplicating problem at shop, has been towed in 4 times in over 85 degree weather after being driven 10 miles and then wont' start. Fuel pump replaced at 2nd tow in.
hey man limited on time trying to figure this 08 g6 out. anyway my question is what if u do not have a 2.5 ref volt at pin 6 and 14? iv got .8 on 14 nd 1.1 on 6. where do i go from there?
@@BrianMann216 thanks man i ran out of daylight today i managed to unplug the bcm nd the vcim aswell as at the dlc checkd ohms on both LAN lines only had 4.5 ohms. what would this indicate? also before i ever took my battery off with key in ignition turned to the run position i check for my 5v signal at my throttle body connector if i remember correctly i had like 1.3 on one of the pins but nothing on the others. im thinkin bad pcm im a decent shadytree mechanic and this one is giving me trouble. thanks
Great video. I have a 95 Mustang with the 5.0 and no communication with dlc. It has MSD ignition and other performance parts. Could the MSD cause a no communication problem ? Thanks
problem facing in Chevrolet captiva 2007 manual, DTC U0073(Control Module Communication Bus OFF), U0121(ABS MODULE lost communication) and P0500(Vehicle Speed Sensor) ,,,,suddenly instrument cluster stops working ,all needles(Temperature, rpm, speed etc.) showing 0 reading , ac stops cooling while blower keep running,reverse gear light stops working, Service Vehicle Soon light & MIL illuminates in cluster. and all happen intermittently and all together. Can anybody suggest solution?
list what modules are setting which DTC, I am assuming the P0500 is in the PCM. I am not familiar with the 2007 Captiva, what country / market was this vehicle sold in
@@BrianMann216 www.autocats.ws/manual/chevrolet/tis0211/en/Documents_2010/Captiva/sm-c/7C2_1F2M.en.html Can please suggest according to above link.exactly what should I do.
Thank you for the video. I'm working on an 08 Uplander with the 3.9. Lost communication with the ecm and tcm. I think the other modules are all communicating. The car is a no crank. The gear indicator light is absent as is the check engine light. Is it likely to be a CAN fault before the ecm leading to no communication with the ecm and tcm
Just wondering how did you come to the conclusion that its a CAN problem , Did the scan tool direct you to this direction from the start? Great Stuff man, Thank you very much.
The scan tool told me we had No communication , the modules that did communicate set codes for no com with the modules that were not talking. A look at the diagram in this case clearly showed me it was a CAN bus problem.. I think back then I was not nearly as familiar with the CAN bus as I am now.
@@BrianMann216 problem facing in Chevrolet captiva 2007 manual, DTC U0073(Control Module Communication Bus OFF), U0121(ABS MODULE lost communication) and P0500(Vehicle Speed Sensor) ,,,,suddenly instrument cluster stops working ,all needles(Temperature, rpm, speed etc.) showing 0 reading , ac stops cooling while blower keep running,reverse gear light stops working, Service Vehicle Soon light & MIL illuminates in cluster. and all happen intermittently and all together. Can anybody suggest solution?
ok brian mann i have a few questions if you dont mind to explain them. i read that in a gm service manual that the can gm high speed can lines are 2 twisted together wires. does that mean there 2 wires twisted together under the wire insulation of the wires on pins 6 and 14?? also could you disconnect all modules and ohm out from end to end of the can wires from where they connect to each module? to check for shorts to grounds,opens short to voltage? thanks!
Just read your comment about ALLDATA, currently looking for better wiring diagrams to help me. How do they compare with the likes of autodata ( if you have used it) do you have access to European vehicle data such as ford,vw,fiat etc
do you mean that when you check the resistor between pin 6 and 14,,,,,,,,,,,,,,,,,,,,,,,,,,,, in any car,,,,,,,,,,,,,,,,, must read 60 ohms which this tell us it is a good CAN BUS, but if it reads 120 ohms,,,,,,,,,,,, in any cars,,,,,,,,,,,,,,,, it is bad.
obviously you know your CAN communication ,modules and schematic ,but the way you explain how to diagnose this vehicle is that you are talking to yourself.Too fast,ambiguous and not clear for average mechanic like me to understand.maybe I am too slow for your explanation.Could you be more specific like you are teaching to a student? Thank you
do you mean that when you check the resistor between pin 6 and 14,,,,,,,,,,,,,,,,,,,,,,,,,,,, in any car,,,,,,,,,,,,,,,,, must read 60 ohms which this tell us it is a good CAN BUS, but if it reads 120 ohms,,,,,,,,,,,, in any cars,,,,,,,,,,,,,,,, it is bad.
This is the first video I have seen that shows a real CAN/BUS diagnosis and repair. Well done.
Actually its the second for me but have a look at this one if you are interested th-cam.com/video/uKnQI2IScPU/w-d-xo.html
Thanks for doing this video. the Cobalt that I got for our daughter for her birthday didn't run when I purchased it. I figured it would be something silly and stupid. Turns out it had three issues. There was a slight fray on the can bus wire leaving the ECU going towards the TCM. That would not allow the data port (obd2) to work. But also the ABS module was bad. While trying to find the cut in the wire that was between the TCM and ecu, I figured out that the ABS module was bad and had to do a patch a couple of clips in the ABS connector to bypass the ABS module. After I got the OBD2 scanner to now communicate with the ecu, the car was still not crank. I happen to have seen another video regarding the ground being bad in the TCM, I literally just took a instead of jumper cables and put the negative side on the TCM and the other negative side onto a ground on the body. Voila, the car started!!
I was very close to feeling beaten. Luckily, I tried the jumper cable as a last resort .
Thanks a lot for the video. It helped me understand the can bus better and how to diagnose it
THAT was fantastic...speaking from experience your technique was flawless. HELL YEAH BROTHA!
My heartfelt appreciation to you for presenting this information in the way that you did. It is complicated but very understandable seeing that a background in electronics is so needed in the auto industry. the newer cars are even more technical, thanks
Learned a lot from this video, thank you.
Terrific diagnosis, strange I hadn't run across this video before. IMHO and only an opinion , I generally break the system at the easiest middle point to check both directions. 2 minutes more of searching the location of all the modules and I'm sure you would have found that problem in half the time. Please understand I'm not knocking. This is a great video and great diagnosis. Not every video has to be geared to a diy guy
I like the video; I need help with my 2011 HHR. I R&R the Transmission when I had the fuse box out, I accidently shorted the main battery cable to ground now I have no crank no start. No power going to the starter solenoid. I looked at everything I can think of and can't find what I smoked.
Thanks for your input I appreciate it. I am thinking of making a more general video on the diagnostics steps that I do on nearly all the vehicles that I work on that are a no start / no crank. Also my camcorder does not work so this was shot with a nikon cool pix camera and I only had a little over 8 min of time to record.
Brian Mann
which wires did you jump to bypass the vcim? I had 30ohms at my can bus pins not sure what would cause that. also my number 1 pin to grouns was like .5volts
Hello Brian can you please tell what wires you used to bypass the VCIM
Did you ever find out what two wires are used to bypass??
damn it i need to know also! lol@@DPjr-zx5pg
I added some die electri grease to the electrical plugs to tcm, ecm,and the fuse box last Saturday 1-7-2023 and my 2008 chevy hhr never cranked again no start no crank it's driving me crazy before I added the die electric grease I didn't try to start the car. It runs great but sometimes the gauges intermittent and then it stops Trans shift hard and stop please help me
What codes are setting. I rarely add dielectric grease to connectors, I have no idea why people think that will fix something. Just makes a slimy mess l!
You did i fine... I followed right along and i pretty much knew where u were going, the first video was tough with no audio. Thanks for reposting so soon wasnt sure if u were going to or not.
I know this is an older video, but anyone else having this issue please check the UBEC connectors as well. There is a known problem with terminals being backed out/not clipped properly causing poor/no contact. 😊👍🏻
I have a crank no start where would be the best place to get wiring schematics. I checked the coil pack no spark on 1&4 crank sensor had voltage. I have replace the fuel pump, check fuses, relys, tps, pulled valve cover valve are rotating, did compression check, blew through fuel line, changed filter.Thanks in advance for any help given.
What color wires are you using to bypass it
My hhr runs but my #16 pin has no power. so the obd can code tester does not communicate with the car. would you know why the#16 has no power??
Please help. Thanks.
Hello. Very good video
Just a thought, if scanner showed no communication with PCM,TCM and EBCM and looking at the diagram you showed,where you can see the EBCM,TCM and PCM in that order in the circuit, wouldn't be a little quicker after knowing that one terminating resistor was not present, to isolate the system first right before the first missing module, in this case the EBCM and check both sides of the circuits at the point of separation ? With the EBCM being hard to get to, it would have pointed you straight to the VCIM .
Just a thought.
Thanks
I would check for codes in all the modules for starters.. you would have to have a decent aftermarket scanner to do this.. on newer vehicles like this if one module goes bad it can cause a no crank / no start
Any advise for a hot weather start problem on a 2006 HHR? Having a problem duplicating problem at shop, has been towed in 4 times in over 85 degree weather after being driven 10 miles and then wont' start. Fuel pump replaced at 2nd tow in.
Good video same problem what 2 wires u jumped help !!!!
hey man limited on time trying to figure this 08 g6 out. anyway my question is what if u do not have a 2.5 ref volt at pin 6 and 14? iv got .8 on 14 nd 1.1 on 6. where do i go from there?
Start disconnecting modules and monitor those voltages.
@@BrianMann216 thanks man i ran out of daylight today i managed to unplug the bcm nd the vcim aswell as at the dlc checkd ohms on both LAN lines only had 4.5 ohms. what would this indicate? also before i ever took my battery off with key in ignition turned to the run position i check for my 5v signal at my throttle body connector if i remember correctly i had like 1.3 on one of the pins but nothing on the others. im thinkin bad pcm im a decent shadytree mechanic and this one is giving me trouble. thanks
?
@@justinlockhart4193 see if you can find a diagram to separate the system and check for 120 ohms to each end
excellent video on a 2012 malibu
what happen if the car is running end jump wire from positive battery to TAN/BLK at D L C connector
Not sure I dont recommend it, CAN should be protected, but you never know.
where do you find the communication module
good tip onboardtech
if you are not a professional/ or have a all data pro, mithcells or identifix sub... i would recommend all data diy for schematics and flow charts
Great video. I have a 95 Mustang with the 5.0 and no communication with dlc. It has MSD ignition and other performance parts. Could the MSD cause a no communication problem ? Thanks
get a challenger
problem facing in Chevrolet captiva 2007 manual, DTC U0073(Control Module Communication Bus OFF), U0121(ABS MODULE lost communication) and P0500(Vehicle Speed Sensor) ,,,,suddenly instrument cluster stops working ,all needles(Temperature, rpm, speed etc.) showing 0 reading , ac stops cooling while blower keep running,reverse gear light stops working, Service Vehicle Soon light & MIL illuminates in cluster. and all happen intermittently and all together. Can anybody suggest solution?
list what modules are setting which DTC, I am assuming the P0500 is in the PCM. I am not familiar with the 2007 Captiva, what country / market was this vehicle sold in
@@BrianMann216 Country INDIA
@@harshkhy Sounds like a Communication issue for sure. I dont have SI ( service info) for a 2007 Captiva
@@BrianMann216 www.autocats.ws/manual/chevrolet/tis0211/en/Documents_2010/Captiva/sm-c/7C2_1F2M.en.html
Can please suggest according to above link.exactly what should I do.
@@BrianMann216 yes it is communication error but till now not able to find cause.
so what happenened did yuo fix it ?
Yes new VCIM and programming fixed that one.
Thank you for the video. I'm working on an 08 Uplander with the 3.9. Lost communication with the ecm and tcm. I think the other modules are all communicating. The car is a no crank.
The gear indicator light is absent as is the check engine light. Is it likely to be a CAN fault before the ecm leading to no communication with the ecm and tcm
Wiring diagram is key chaps! Nice video, good elimination technique. Did I say wiring diagram was key? ;-)
How would it communicate by jumping the CAN wires while the VCIM is out the pictures?
Thx great video
the vcim is not necessary for other modules to communicate with each other, but it was pulling down the entire netwrok
What's the color of wires you jump?
Just wondering how did you come to the conclusion that its a CAN problem , Did the scan tool direct you to this direction from the start?
Great Stuff man, Thank you very much.
The scan tool told me we had No communication , the modules that did communicate set codes for no com with the modules that were not talking. A look at the diagram in this case clearly showed me it was a CAN bus problem.. I think back then I was not nearly as familiar with the CAN bus as I am now.
Crystal clear man...Thank you very much..👍👍
@@BrianMann216 problem facing in Chevrolet captiva 2007 manual, DTC U0073(Control Module Communication Bus OFF), U0121(ABS MODULE lost communication) and P0500(Vehicle Speed Sensor) ,,,,suddenly instrument cluster stops working ,all needles(Temperature, rpm, speed etc.) showing 0 reading , ac stops cooling while blower keep running,reverse gear light stops working, Service Vehicle Soon light & MIL illuminates in cluster. and all happen intermittently and all together. Can anybody suggest solution?
ok brian mann i have a few questions if you dont mind to explain them. i read that in a gm service manual that the can gm high speed can lines are 2 twisted together wires. does that mean there 2 wires twisted together under the wire insulation of the wires on pins 6 and 14?? also could you disconnect all modules and ohm out from end to end of the can wires from where they connect to each module? to check for shorts to grounds,opens short to voltage? thanks!
phil holbrook Want me to answer this yet? 😁
Yes absolutely
Just read your comment about ALLDATA, currently looking for better wiring diagrams to help me. How do they compare with the likes of autodata ( if you have used it) do you have access to European vehicle data such as ford,vw,fiat etc
Yo tengo el problema parecido pero no tengo corriente En el fusible 41 y 45 del hhr 2008
Nice work!
do you mean that when you check the resistor between pin 6 and 14,,,,,,,,,,,,,,,,,,,,,,,,,,,, in any car,,,,,,,,,,,,,,,,, must read 60 ohms which this tell us it is a good CAN BUS, but if it reads 120 ohms,,,,,,,,,,,, in any cars,,,,,,,,,,,,,,,, it is bad.
Should be a little high than 2.5volts on Can + and slightly lower than 2.5volts on Can -
Nice video! Keep the can faults coming!
hello how are u.
obviously you know your CAN communication ,modules and schematic ,but the way you explain how to diagnose this vehicle is that you are talking to yourself.Too fast,ambiguous and not clear for average mechanic like me to understand.maybe I am too slow for your explanation.Could you be more specific like you are teaching to a student?
Thank you
Have similar issues with cobalt. Checked through the system it had 60 ohms at the dlc when I put it back together. Got the U2100 on the test drive
do you mean that when you check the resistor between pin 6 and 14,,,,,,,,,,,,,,,,,,,,,,,,,,,, in any car,,,,,,,,,,,,,,,,, must read 60 ohms which this tell us it is a good CAN BUS, but if it reads 120 ohms,,,,,,,,,,,, in any cars,,,,,,,,,,,,,,,, it is bad.