White Bread
Member
- Joined
- Dec 18, 2023
- Messages
- 21
- Location
- Tampa
- V-Series Cadillac(s)?
- '24 CT4-V BW - Cyber Yellow - 6 spd.
*Updated as of 1146ET on 4/24*
Figured I'd take to the forums to share my current experience and also (hopefully) learn from others. I'll continue to update this thread as things progress.
TL;DR:
My 2024 CPO 4BW (purchased with 400 miles in mid-December) has been in service with Cadillac for 28 days as of today (took it in on March 27th) due to an electrical issue, and despite throwing numerous parts/fixes at it, and involving GM field engineers, they still cannot resolve the issue.
Detailed explanation
The symptoms/issue:
I purchased the car in mid-December as a CPO with ~400 miles on the clock. About 45 days into ownership it started exhibiting some odd electrical behavior. At random, the gauge cluster would light up like the proverbial Christmas tree with all kinds of errors (service rear axle, TSC not available, take control of steering, etc.) At the same time the errors present, the cluster immediately loses all input signals. I could be driving around town at 45 mph and the cluster would show 0 mph, 0 rpm, 0 fuel, 0 oil pressure... you get the idea. While all of this is occurring, the HVAC cranks to full blast max heat, regardless if it was off or on with the A/C set to 68 degrees. The turn signals nor brake lights will work, it puts the car into tour mode and closes the exhaust valves and limits the top speed to 62 mph. Video:
The first time this happened was late in the evening driving home from dinner. Because it closed the exhaust valves and showed 0 inputs on the gauge cluster, I thought the car actually shut off (when it hadn't). As such, I coasted to a stop and hit the start/stop button and it did nothing. I couldn't even jump the car. It was like it was in some sort of limbo mode where it wasn't getting signals that I was actually trying to start it. After about 20 minutes it "reset" itself and I was able to start it up and drive it home.
Again, this behavior happens at complete random intervals. After the first instance, it didn't do it again for another week. Then it went 2-3 weeks. Other times it would do it multiple times over the course of a 15-20 minute drive. Battery voltage always seemed normal - I never noticed any significant fluctuations via the readings in the gauge cluster. What's more, it seemed to do it while the car was off as well. There were several occurrences where I'd go out to start the car in the morning, after having no symptoms the previous day, and it just wouldn't turn on. Again, it acted like the signal to start it wasn't even being initiated. During these times where I couldn't get it to even start (wouldn't even crank, gauge cluster wouldn't turn on, etc.), the brake lights wouldn't work, turn signals, etc. After a few minutes, it would randomly come back to life.
When these episodes would occur, it would throw a CEL with the following codes: P25A2, P0A43, P04C0, U0073, U1611, C0701. After a few starts/restarts, the codes would clear.
The challenge with this whole thing is the randomness with which it would occur. Because of this, I was not able to get it into the dealer until March 27th (I'll spare you the details of my work schedule). What I didn't want was to take it all the way down there (40 minutes) to have them tell me they couldn't recreate the issue and then send me on my way. Thankfully, that hasn't been the case since they've had it.
The time in service:
The morning of March 27th it took about 10 minutes to finally get it started and on the way to drop the kids at school, the errors came and went, gauge cluster lost input signals and then they came back, etc. Since I had a light day, I called to ensure the dealer could get me in a loaner/rental and then took it in for them to look at. Naturally, it stopped exhibiting the loss of signal behavior when I arrived, but the CEL/codes were still present and they were able to scan and document them.
Fix 1:
They were actually able to recreate the behavior of the gauge cluster losing inputs later in the day and started their investigative work. On Friday morning (3/29), 2 days after I dropped it off, the service advisor (SA) called and said they updated the BCM module and fixed a faulty ground wire/strap on the rear diff. and that it was ready to be picked up. When I got there and went to start the car, it started doing the same thing (wouldn't start, etc.). Went back in and the SA called the technician and I can hear him on the other end of the phone saying "what in the literal f*ck?!" Left the car with them to continue investigating.
Fix 2:
On 4/2, my SA advised that they had to open a case with GM and GM wanted them to test the vehicles wiring, thinking it was either an issue with the main bus line or an internal fault with the rear diff module. Wiring tests came back normal so GM advised to replace the rear diff module. Part finally came in and on 4/8 they advised the replacement did not fix the issue. At this point they decided to put me in a brand new XT4 loaner instead of the 50k mile Malibu through Enterprise. They also indicated that they were going to schedule a GM field engineer (FE) to come onsite and look at the car.
Fix 3:
No updates for over a week and then on 4/16 my SA explains that the FE thinks there's an issue with a harness associated to the rear diff module and that there were a few tests they needed to run to confirm, and they should know more tomorrow (4/17). Tomorrow comes and goes and I finally reach out on Friday afternoon (4/19) for an update. Apparently the harness checked out fine and they now had a serial data gateway module on order, and that they are "hoping" this will fix the issue.
I called and spoke to the service manager yesterday (4/23) who indicated the new module arrived on Monday, the tech was in the process of installing it and that after testing a few times they'd let me know the results. I tracked them driving it twice yesterday via the Cadillac app, and low and behold, after the second drive the app is showing the car has several service-related warnings/issues again. As of the writing of this post (morning of 4/24) I have not spoken to them about what the replacement of the serial data module yielded, and what our next steps are (though I can guess).
*Update 4/24* I finally spoke to the Service Manager later this morning (4/24) and I was right, the new module did nothing to fix the car. They're now waiting on GM to schedule another visit for a FE but cannot give me any ETA.
*Update 4/30* After reading through the responses to this thread (thank you everyone) I opened a case with Cadillac support and the BBB Auto Line. I spoke with a buyback rep from Cadillac/GM yesterday and I should know if the buyback/replacement is approved on Thursday or Friday of this week.
My questions for the greater group revolve around what my recourse is here. Because the car was purchased as a used car, the Florida Lemon Law does not apply, though I'm told I can still seek recourse through the Magnuson-Moss act. I've spoken with an attorney who has indicated that once the car has been in service for 30 consecutive days, we can start to seek action from GM; but to what degree I'm not yet familiar.
At what point does GM throw in the towel and offer to buy the car back? Will that only come if I press the legal button, or would they proactively offer that? I'm really to the point where I don't want the car back. Lord knows what they've had to take off, remove, reassemble then disassemble again to get to these different modules, harnesses or wire runs. I've also lost all confidence in their ability to identify the root cause. What, if after all of this the car suddenly stops doing it for 2 weeks (like it usually does) they hand it back, and then it does it again?
Figured I'd take to the forums to share my current experience and also (hopefully) learn from others. I'll continue to update this thread as things progress.
TL;DR:
My 2024 CPO 4BW (purchased with 400 miles in mid-December) has been in service with Cadillac for 28 days as of today (took it in on March 27th) due to an electrical issue, and despite throwing numerous parts/fixes at it, and involving GM field engineers, they still cannot resolve the issue.
Detailed explanation
The symptoms/issue:
I purchased the car in mid-December as a CPO with ~400 miles on the clock. About 45 days into ownership it started exhibiting some odd electrical behavior. At random, the gauge cluster would light up like the proverbial Christmas tree with all kinds of errors (service rear axle, TSC not available, take control of steering, etc.) At the same time the errors present, the cluster immediately loses all input signals. I could be driving around town at 45 mph and the cluster would show 0 mph, 0 rpm, 0 fuel, 0 oil pressure... you get the idea. While all of this is occurring, the HVAC cranks to full blast max heat, regardless if it was off or on with the A/C set to 68 degrees. The turn signals nor brake lights will work, it puts the car into tour mode and closes the exhaust valves and limits the top speed to 62 mph. Video:
The first time this happened was late in the evening driving home from dinner. Because it closed the exhaust valves and showed 0 inputs on the gauge cluster, I thought the car actually shut off (when it hadn't). As such, I coasted to a stop and hit the start/stop button and it did nothing. I couldn't even jump the car. It was like it was in some sort of limbo mode where it wasn't getting signals that I was actually trying to start it. After about 20 minutes it "reset" itself and I was able to start it up and drive it home.
Again, this behavior happens at complete random intervals. After the first instance, it didn't do it again for another week. Then it went 2-3 weeks. Other times it would do it multiple times over the course of a 15-20 minute drive. Battery voltage always seemed normal - I never noticed any significant fluctuations via the readings in the gauge cluster. What's more, it seemed to do it while the car was off as well. There were several occurrences where I'd go out to start the car in the morning, after having no symptoms the previous day, and it just wouldn't turn on. Again, it acted like the signal to start it wasn't even being initiated. During these times where I couldn't get it to even start (wouldn't even crank, gauge cluster wouldn't turn on, etc.), the brake lights wouldn't work, turn signals, etc. After a few minutes, it would randomly come back to life.
When these episodes would occur, it would throw a CEL with the following codes: P25A2, P0A43, P04C0, U0073, U1611, C0701. After a few starts/restarts, the codes would clear.
The challenge with this whole thing is the randomness with which it would occur. Because of this, I was not able to get it into the dealer until March 27th (I'll spare you the details of my work schedule). What I didn't want was to take it all the way down there (40 minutes) to have them tell me they couldn't recreate the issue and then send me on my way. Thankfully, that hasn't been the case since they've had it.
The time in service:
The morning of March 27th it took about 10 minutes to finally get it started and on the way to drop the kids at school, the errors came and went, gauge cluster lost input signals and then they came back, etc. Since I had a light day, I called to ensure the dealer could get me in a loaner/rental and then took it in for them to look at. Naturally, it stopped exhibiting the loss of signal behavior when I arrived, but the CEL/codes were still present and they were able to scan and document them.
Fix 1:
They were actually able to recreate the behavior of the gauge cluster losing inputs later in the day and started their investigative work. On Friday morning (3/29), 2 days after I dropped it off, the service advisor (SA) called and said they updated the BCM module and fixed a faulty ground wire/strap on the rear diff. and that it was ready to be picked up. When I got there and went to start the car, it started doing the same thing (wouldn't start, etc.). Went back in and the SA called the technician and I can hear him on the other end of the phone saying "what in the literal f*ck?!" Left the car with them to continue investigating.
Fix 2:
On 4/2, my SA advised that they had to open a case with GM and GM wanted them to test the vehicles wiring, thinking it was either an issue with the main bus line or an internal fault with the rear diff module. Wiring tests came back normal so GM advised to replace the rear diff module. Part finally came in and on 4/8 they advised the replacement did not fix the issue. At this point they decided to put me in a brand new XT4 loaner instead of the 50k mile Malibu through Enterprise. They also indicated that they were going to schedule a GM field engineer (FE) to come onsite and look at the car.
Fix 3:
No updates for over a week and then on 4/16 my SA explains that the FE thinks there's an issue with a harness associated to the rear diff module and that there were a few tests they needed to run to confirm, and they should know more tomorrow (4/17). Tomorrow comes and goes and I finally reach out on Friday afternoon (4/19) for an update. Apparently the harness checked out fine and they now had a serial data gateway module on order, and that they are "hoping" this will fix the issue.
I called and spoke to the service manager yesterday (4/23) who indicated the new module arrived on Monday, the tech was in the process of installing it and that after testing a few times they'd let me know the results. I tracked them driving it twice yesterday via the Cadillac app, and low and behold, after the second drive the app is showing the car has several service-related warnings/issues again. As of the writing of this post (morning of 4/24) I have not spoken to them about what the replacement of the serial data module yielded, and what our next steps are (though I can guess).
*Update 4/24* I finally spoke to the Service Manager later this morning (4/24) and I was right, the new module did nothing to fix the car. They're now waiting on GM to schedule another visit for a FE but cannot give me any ETA.
*Update 4/30* After reading through the responses to this thread (thank you everyone) I opened a case with Cadillac support and the BBB Auto Line. I spoke with a buyback rep from Cadillac/GM yesterday and I should know if the buyback/replacement is approved on Thursday or Friday of this week.
My questions for the greater group revolve around what my recourse is here. Because the car was purchased as a used car, the Florida Lemon Law does not apply, though I'm told I can still seek recourse through the Magnuson-Moss act. I've spoken with an attorney who has indicated that once the car has been in service for 30 consecutive days, we can start to seek action from GM; but to what degree I'm not yet familiar.
At what point does GM throw in the towel and offer to buy the car back? Will that only come if I press the legal button, or would they proactively offer that? I'm really to the point where I don't want the car back. Lord knows what they've had to take off, remove, reassemble then disassemble again to get to these different modules, harnesses or wire runs. I've also lost all confidence in their ability to identify the root cause. What, if after all of this the car suddenly stops doing it for 2 weeks (like it usually does) they hand it back, and then it does it again?
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