CT4BW's Turning Off - Safety Risk

[cgdigisco]

Do we know if everyone who this has happened to had something plugged in to the port? Or if everyone has a specific option selected? It would be great if we could come together to try and diagnose a consistent cause

 

[Furinax]

Many owners do not participate in either FB or this forum.

It seems quite unlikely that we’re aware of 100% of incidence of this failure.

I picked a 4bw instead of an Alfa to get away from shit exactly like this.

Like others, my toddler son was a huge part of why I needed a 4 door.

Please, GM, the car is fantastic. Don’t force us to buy M3s. I don’t want to drive an M car. Do the right thing GM.

The fact that a dealer wants to blame an insurance dongle is either immoral or idiotic. How on earth could an OBDII reader disrupt steering and brakes? I thought Global B was a cybersecurity marvel.

The wire harness recall seems unrelated.

The repeated failures of specified replacement parts, in conjunction with service department’s inability to describe the issue with any clarity whatsoever, is also pretty concerning.

It would seem GM has no idea what’s causing this and won’t admit it.

God forbid something happens to a driver, they’re cooked. Unfortunately, it seems inevitable, given the nature of the failures.

We’ve all bought GM’s trophy luxury supersedan, and they’re failing dangerously. Shit happens, but we deserve to be communicated to proactively.

Look at how porsche caters to gt3 clientele.

Alfa played this game with the first gen QV 2.9L v6tt engines in the US. They failed rampantly, and Alfa would just take the motor and ship it unopened to Italy for autopsy. They’d replace it and never tell owners what failed. 2 years later, they revised the cars to get a dual injection revision of same engine, without advertising the change at all. The reliability improved considerably from then on.

Many felt there should have been a recall and swap, but it’s been dealt with case by case.

GM: no one wants class actions and lemon laws. Just talk to us candidly and fix it.

Maybe throw in a free track day

Amen brother. I enjoy this car so much yet I drive with a dashcam now so I can catch the inevitable loss of brakes again. I don't think the techs really feel like it's their responsibility to solve this problem. For them they just follow the manual.

I think the only way for them to nail down this problem is to find steps to reproduce it. For now we can only leave the OBD2 unplugged and see what the next answer is when it inevitably happens.

Edit: I noticed it says you are in NJ. Where at? I saw a black 4BW in West Windsor today speed by a ZL1 Camaro. Second 4BW I've seen in the wild.

 

[NJ4BW]

Amen brother. I enjoy this car so much yet I drive with a dashcam now so I can catch the inevitable loss of brakes again. I don't think the techs really feel like it's their responsibility to solve this problem. For them they just follow the manual.

I think the only way for them to nail down this problem is to find steps to reproduce it. For now we can only leave the OBD2 unplugged and see what the next answer is when it inevitably happens.

Edit: I noticed it says you are in NJ. Where at? I saw a black 4BW in West Windsor today speed by a ZL1 Camaro. Second 4BW I've seen in the wild.

I’m in Weehawken although I’m frequently back and forth between westfield and Weehawken ferrying my toddler to his grandma.

 

[kamome97]

Add me to the list. Happened twice. Dealer cleared codes and said it could be what was plugged in my OBD port (which is just a GPS tracker/code reader). Still no leads yet?

 

[dinkman]

i dont get why the engine wire harness contact recall keeps getting dismissed. that def feels like it could cause these symptoms. has anyone who had the recall addressed had this happen to their car AFTER?

 

[dstewart51]

Its looking like, OBD2 accessories may be affecting the CAN bus causing communications errors with various modules.

 

[dinkman]

Its looking like, OBD2 accessories may be affecting the CAN bus causing communications errors with various modules.

i know one users dealer suggested that was the issue but that theory sounds as solid as a turbine air intake booster will increase hp/improve gas mileage

 

[kamome97]

i dont get why the engine wire harness contact recall keeps getting dismissed. that def feels like it could cause these symptoms. has anyone who had the recall addressed had this happen to their car AFTER?

This is a good point: I got the recall repair done on October 4, 2023, never saw this issue before. The first time I saw this issue was on October 27, and I saw it again on November 20. I had the car for a full year prior to this.
My dealer also suggested CAN devices being an issue, and yes I do have an OBD device but it's literally just a Bouncie. If that truly is the reason then I think that's arguably worse that I can't use my car with normal OBD devices.

 

[kamome97]

This is also worth noting: Both times this happened, I hadn't used the car in a few days:
I was gone from October 20-26th and November 16-19th leaving the car inactive for at least 3 days before this issue happened. But I feel like if this were the reason, I'd see these issues as soon as I started the car up.
But prior to this, I've definitely let the car sit for long periods of time.

 

[dinkman]

This is a good point: I got the recall repair done on October 4, 2023, never saw this issue before. The first time I saw this issue was on October 27, and I saw it again on November 20. I had the car for a full year prior to this.
My dealer also suggested CAN devices being an issue, and yes I do have an OBD device but it's literally just a Bouncie. If that truly is the reason then I think that's arguably worse that I can't use my car with normal OBD devices.

damn there goes the recall theory
this sucks bro, sorry to hear

 

[Nanci CT4 Blackwing]

Happened to me in TWO DIFFERENT CARS. The first time was in May 2023 in a 2022 CT4 V. They claim they fixed it then it happened again in October. I refused to drive the car. They took it back (with a small loss to me) and I leased a 2023 CT4 V Blackwing. Just happened again today. The dealer acts like I am the only one it has happened to.

 

[BWDudeBro]

I checked carfax and my car shows this recall, but i haven't gotten a letter yet. I'm the second owner but I got the car with just 300mi on it.

I looked around under the hood and thought I had identified the area in question, but I'm not so sure. I'm a little surprised there aren't yet pics (from owners or GM) of the affected area.

 

[cgdigisco]

Happened to me in TWO DIFFERENT CARS. The first time was in May 2023 in a 2022 CT4 V. They claim they fixed it then it happened again in October. I refused to drive the car. They took it back (with a small loss to me) and I leased a 2023 CT4 V Blackwing. Just happened again today. The dealer acts like I am the only one it has happened to.

You should show them this thread. I'm sorry this happened to you, Im sure that is very frustrating. Were there any options both cars had that could maybe contribute to this? PDR, any sort of plug in, etc.

 

[raptor5244]

I checked carfax and my car shows this recall, but i haven't gotten a letter yet. I'm the second owner but I got the car with just 300mi on it.

I looked around under the hood and thought I had identified the area in question, but I'm not so sure. I'm a little surprised there aren't yet pics (from owners or GM) of the affected area.

FWIW, I had the recall done a couple weeks ago. It is in tough spot to get to at the back of the engine near the firewall. The tech had to take the cowl and wipers off just to be able to inspect behind there yet alone install the protective sleeve and zip-tie the harness away from the brake line. Took about 2 hours for them to do the work.

 

[BWDudeBro]

FWIW, I had the recall done a couple weeks ago. It is in tough spot to get to at the back of the engine near the firewall. The tech had to take the cowl and wipers off just to be able to inspect behind there yet alone install the protective sleeve and zip-tie the harness away from the brake line. Took about 2 hours for them to do the work.

Ah, that makes sense.... good intel and thanks for the detail.

I found the only place I could see with both a brake line and a bundle of wiring near each other... Right around the brake master cylinder/ fluid res, but sounds like this is buried behind the motor.

 

[Nanci CT4 Blackwing]

You should show them this thread. I'm sorry this happened to you, Im sure that is very frustrating. Were there any options both cars had that could maybe contribute to this? PDR, any sort of plug in, etc.

Yes, there was an Allstate Milewise plug in. But it is the same story with everyone else, they can't recreate the problem. Twice in the 2022 CT4V and once in the CT4VBW. They are now telling me that a GM engineer is going to come and look at it, after the first of the year. I printed out the thread and gave it to the service department when they towed the car in. The BW only has about 500 miles. Someone is going to get killed.

 

[cgdigisco]

Yes, there was an Allstate Milewise plug in. But it is the same story with everyone else, they can't recreate the problem. Twice in the 2022 CT4V and once in the CT4VBW. They are now telling me that a GM engineer is going to come and look at it, after the first of the year. I printed out the thread and gave it to the service department when they towed the car in. The BW only has about 500 miles. Someone is going to get killed.

So far, that’s the only thing I’ve seen consistently among these cases - plug ins are the only similarities. It’s a dangerous situation for sure, I’m sorry you’re going through it. I didn’t realize it was happening to the 4Vs though too, I thought only the BWs.

What was their reaction when they read the thread? Did it add a little urgency to it?

 

[White Bread]

Not sure how related my scenario is but coming home last night my dash lit up and the engine completely shut down (thankfully we were in the neighborhood already).

Started throwing lots of errors on the dash (like service axle). HVAC shot up to full blast and I couldn’t shut off the parking lights. I could not get the car to start after that.

I was able to jump start it and drive it down the road to the house but the digital cluster now doesn’t do anything. Like it’s on but rpms and speed don’t move, doesn’t show what gear I’m in, mileage just shows ————— and it says my fuel tank is completely empty.

I’m baffled. Stock car with 800 miles

 

[White Bread]

Not sure how related my scenario is but coming home last night my dash lit up and the engine completely shut down (thankfully we were in the neighborhood already).

Started throwing lots of errors on the dash (like service axle). HVAC shot up to full blast and I couldn’t shut off the parking lights. I could not get the car to start after that.

I was able to jump start it and drive it down the road to the house but the digital cluster now doesn’t do anything. Like it’s on but rpms and speed don’t move, doesn’t show what gear I’m in, mileage just shows ————— and it says my fuel tank is completely empty.

I’m baffled. Stock car with 800 miles

I left the negative terminal off the battery last night. Just went out and reconnected it and the car started right up. No CEL or errors are present. The digital cluster also works as normal. WTF

 

[BWDudeBro]

I left the negative terminal off the battery last night. Just went out and reconnected it and the car started right up. No CEL or errors are present. The digital cluster also works as normal. WTF

Yikes. A lot of the symptoms I've heard sound like what might happen if a critical CAN issue was going on... like if a tiny wire in just the right place was cut or grounding where it wasn't supposed to. But the fact this "corrected" itself after a reset like that is odd.

Although if there's one thing I've learned in my years working on cars, it's that electricity is a dark art and even more so when applied to dozens of tiny computers in a car.