CT4BW's Turning Off - Safety Risk

[blvckwing]

I haven't seen this posted about here, so forgive me if I'm beating a dead horse.

A few days ago while driving (45mph), my 22' 4BW dash lit up like hell and I lost power steering, brakes, went into limp mode. Restarted the vehicle, all was well. I did almost take out the Mini Cooper in front of me, with a 'Baby on Board' sticker. Don't even want to think about that. I have a service appointment scheduled for next week and I'm not driving the vehicle until then.

The conversations occurring in the ATSV/CT4BW FB groups were brought to my attention - check out this screenshot:

These guys had it happen within the last 2-3 weeks. Counting myself, I know of two other people that this has happened to, one of whom ended up in a major car accident because of it. That makes 6..

I'm the only one out of the collection that is not stock (ie, downpipes), but I'm really not even remotely under the impression that this would be any sort of a factor, especially in the face of others coming out of the woodwork.

If this has happened to anyone on this forum, please do share your experience.

Thanks!

 

[Grainofsand]

Are you saying this happened to more than 1 person?

 

[blvckwing]

Are you saying this happened to more than 1 person?

Hi Jaymes,

Yes. The screenshot alone has 3 different people describing the same thing occurring to them within 7 days of each other. I personally know more folks it's happened to, myself included.

 

[Tall Steve]

 

[Head Hunter]

Is it only being reported on 4BW? Not 4V or 5V/BW?

 

[blvckwing]

Yes, only on the 4’s that I can see.

Another user on the Facebook thread chimed in, states that the same thing happened to them with a baby in the car.

That’s like 7 people (that I know of) within a very small timeframe. I did not get any OTA updates that I am aware of.

Original poster took their car to the dealership and it was revealed that the car threw 28 codes at the time of failure. Master tech currently diagnosing.

Seriously concerned about this, contemplating getting rid of the car if Cadillac doesn’t have a clearly stated cause+solution.

 

[Barstoolman1127]

My son had this happen on his Land Rover years ago. Very dangerous and ultimately had the lemon law vehicle.

 

[Furinax]

Another user on the Facebook thread chimed in, states that the same thing happened to them with a baby in the car.

Yup that was me. It has really drastically lowered my confidence in the car... though that was the only issue I've had with the car other than the alarm going off a few times in the middle of the night.

Mine was the same way. I was driving for a good while (maybe like 20 ish minutes) just trying to put my baby to sleep. While I was driving my dash lit up; it never shut off. My steering was stiff, the brakes were much harder, and the CEL went on. I got a picture of the errors I had while it happened. The biggest issue was with the brakes because I had to slam them in order to stop normally since there was no brake boost. Power steering going off didn't affect me that bad. After parking, I couldn't set the e-brake which is another big no-no. I turned the car on and off after parking and the CEL didn't go away. The next day I turned the car on and the e-brake, steering assist, brake assist all worked again, so I moved it out of my driveway into a spare spot and chocked the wheels.

I meant to get the codes but I never got around to it. The CEL went away after a week and I just did another 1 hr drive today to put the baby to sleep with no problems. My car is completely stock (under 3k miles) and has only been worked on by the dealership. I'll definitely mention it on my next visit, which I will be going in person for. This is a serious concern for me because I specifically bought this car to transport a baby around!

 

[savethemanual]

Wonder if this is related to the engine power harness issue.

https://gmauthority.com/blog/2023/04/some-cadillac-ct4-v-blackwing-units-will-get-an-engine-wiring-harness-fix/amp/

 

[blvckwing]

Yup that was me. It has really drastically lowered my confidence in the car... though that was the only issue I've had with the car other than the alarm going off a few times in the middle of the night.

Mine was the same way. I was driving for a good while (maybe like 20 ish minutes) just trying to put my baby to sleep. While I was driving my dash lit up; it never shut off. My steering was stiff, the brakes were much harder, and the CEL went on. I got a picture of the errors I had while it happened. The biggest issue was with the brakes because I had to slam them in order to stop normally since there was no brake boost. Power steering going off didn't affect me that bad. After parking, I couldn't set the e-brake which is another big no-no. I turned the car on and off after parking and the CEL didn't go away. The next day I turned the car on and the e-brake, steering assist, brake assist all worked again, so I moved it out of my driveway into a spare spot and chocked the wheels.

I meant to get the codes but I never got around to it. The CEL went away after a week and I just did another 1 hr drive today to put the baby to sleep with no problems. My car is completely stock (under 3k miles) and has only been worked on by the dealership. I'll definitely mention it on my next visit, which I will be going in person for. This is a serious concern for me because I specifically bought this car to transport a baby around!

I’m very happy to hear that you and yours are safe and sound. It’s a very interesting issue and all speculation points to wiring problems. I will ask about the harness as the user above me pointed out next time I go in.

Here are the codes mine threw - Not sure if they’re of any use to anyone:

 

[GT325]

Sounds very scary especially if this is a pervasive issue. Glad nobody was injured. I would suggest filing a report with NHTSA:

Report a Safety Problem | NHTSA

File a complaint with NHTSA if you experienced a vehicle, tire, car seat or equipment safety problem that could be a safety defect.

www.nhtsa.gov

 

[blvckwing]

update: dealership found no faults in the vehicle. called it a 'software glitch'. on my drive home, the car did the same thing, but this time I lost brakes and power steering while doing 80mph on the highway. it's a good thing that I've driven some very unreliable vehicles in my time, and know how to compensate for loss of computer, or I wouldn't be writing this right now.

I love this platform, I love the car, I've wanted a V for most of my life, and I was the happiest person ever when I finally took delivery.

Unfortunately, I need to get rid of the car, it's a no brainer and Cadillac doesn't care that this is happening to quite a few of us. I guess I'll end up halfway happy in an m3 or something, because this is a joke. really disappointed.

 

[Furinax]

Thanks for the update. I've got my appointment scheduled in July. Let me see if I have any luck with them.

Depending on how I am treated I may echo your sentiments.

I too love this car but this is an alarming safety issue. So far it hasn't happened again though, and I went on a road trip and also drive the car to work.

 

[Lithoss]

Anything aftermarket installed at all? I'm not familiar with what JB4 does

 

[Head Hunter]

update: dealership found no faults in the vehicle. called it a 'software glitch'. on my drive home, the car did the same thing, but this time I lost brakes and power steering while doing 80mph on the highway. it's a good thing that I've driven some very unreliable vehicles in my time, and know how to compensate for loss of computer, or I wouldn't be writing this right now.

I love this platform, I love the car, I've wanted a V for most of my life, and I was the happiest person ever when I finally took delivery.

Unfortunately, I need to get rid of the car, it's a no brainer and Cadillac doesn't care that this is happening to quite a few of us. I guess I'll end up halfway happy in an m3 or something, because this is a joke. really disappointed.

In my experience this goes above the dealership. You need to have lemon law conversations with an attorney and start making calls to corporate customer service.

I had far more success dealing with FCA customer service and getting what I wanted then I did from the dealership when we had issues with the wife’s 22 Jeep GW

 

[Furinax]

My car is stock.

 

[rubberduck]

Also interesting to note that the first time it happened, the car was only in limp mode until it was restarted. This time, the car was governed strictly at 62mph and throwing codes for suspension as well as showing malfunctioning sensors for pretty much everything you can think of - brakes, knock, suspension, collision sensor, etc etc. These were obviously not real problems, there's a ghost in the wires

Sounds like a power supply or grounding issue.

 

[savethemanual]

Did any of you ask the dealer to check if it was the engine harness issue?

https://gmauthority.com/blog/2023/04/some-cadillac-ct4-v-blackwing-units-will-get-an-engine-wiring-harness-fix/amp/

Mine was this.

 

[Furinax]

So I finally got around to taking it to the dealership for an oil change and diagnosis. I had to drop the car for 2 days for them to diagnose. They are ordering a new brake system control module under warranty to remedy the situation. I'll have to ask them their reasoning but I sincerely hope the issue doesn't come back. The car was left at the dealership until the module comes in which is about 5 days.

 

[Seth]

Mine did something similar early on in ownership, also "fixed" by turning off and back on. Dealership said it was due to low voltage to MAP sensor which was replaced. Never happened again.