Collision Prevention Assist Plus Inoperative
 

My 2016 GT-S threw this message on the center dashboard today on the freeway. At first it alternated with another message which I forget. The entire center of the dashboard was "seized" and I could not bring up anything else whether it be speed or whatever. The cruise control was also disabled. In a few exits I pulled off to get some gas and when the car started up again the computer reset itself. I saw that this has been a problem with some other models which took a 2-3 hour software update to fix.

I called my dealership and the service adviser looked up my VIN and said there is no campaign about it and no software update is shown as needed. She seemed to think that the restart was sufficient and all is fine. I don't. At very least it is disconcerting and potentially hazardous. At any rate I have a service appointment scheduled for tomorrow. At least they can pull the code.

Has anyone else had this experience with this model?

I also posted this in the AMG Private Lounge.


https://cimg2.ibsrv.net/gimg/www.mbw...4772103ccc.jpg

I have been driving mine since last July and have not had any such messages on mine. Once in a great while I will purposely close on a vehicle while covering the brake to test the system and it tries to stop me very time. I just intercede as soon as the system starts to react.

Sounds like you have an issue with the compukor.

On my W222 they quit working on a long trip.. result was the rain and fog prevented the camera and radar from working. After getting out of the rain, worked fine.

I had a persistent message of "Collision Prevention Assist Plus Inoperative" on my E-Class (message could be cleared from steering wheel buttons but would reappear next time the car was started). I brought the car to the dealer and they found that one of the sensors had lost its data connection with the main data bus. They "just" had to re-stare several processors in the proper sequence to restore communication. It has been a few months since this "re-boot" and all has been well.

Lol, I didn't even know my car had this (2016 AMG GT S), til it came on one time haha, pretty cool!

I got my car back today. Long story short, they couldn’t find anything to really hang this on. I have a copy of the “Initial quick test log” which shows all the codes most of which are benign, but when the car gave the message on the dashboard, it threw 3 specific codes tied to that event. I have scanned them below for your reading pleasure.

The service manager and the AMG tech who did the work said that they wonder if the problem could have been due to the proximity of my radar detector. They both have had some problems with customers related to radar detectors. They wanted to know if mine was on at the time and I said, “yes.” Whether that had something to do with it or not is unknown. They thought maybe that its response to something might have scrambled something and caused the MB system to freak out. There are a lot of “somethings” because the fault codes cleared upon restart and are not able to be duplicated. I have used a radar detector in the car for two months so one wonders as to why now it might have been the cause. But they seemed quite sincere and didn’t have anything definitive. There was nothing to fix.

All this data has been transmitted to MB and AMG they say - so we will see if it happens again. It is a relief to know that a restart clears it. Looking over the data in the print outs didn't say anything too specific or meaningful to me. The dash message is at the end.


https://cimg3.ibsrv.net/gimg/www.mbw...5c4aa83ce1.jpg

These are the first two fault codes


https://cimg4.ibsrv.net/gimg/www.mbw...05105a854e.jpg

This is the third fault code


https://cimg8.ibsrv.net/gimg/www.mbw...beffba8514.jpg

I have a c300 and have been battling this issue. When the "Collision Prevention Assist Plus Inoperative" message appears I lose the ability to accelerate - dangerous stuff. However, an error code did appear when the service department ran a diagnostic (see link to post below with more detail) Car is still in the shop (dropped it off on 4/7!) and the MB service manager called me today (still test driving the vehicle) and stated the new fix issued from HQ is to replace all the sensors along the front of the vehicle so that they fit more securely = better connection. The various service departments go between this error being purely a software issue (that was my first "fix"), to a mechanical issue (the new "fix") - they really need to figure it out before someone is seriously injured or killed.

The NHTSA website if chock full of these complaints...

https://mbworld.org/forums/c-class-w...operative.html

I am glad that my car's control was not impeded like yours. I was able to accelerate. BTW, do you use a radar detector?

Nope, no radar detector.

My valentine radar detector would go off sometimes due to other cars, I was on a long highway trip one time and everytime this new 7 series bmw got close it would go off, that was in my Porsche 997

My old Valentine would also. But the new ones have Junk-K fighter built in so it doesn't go off being close to cars with lane-change or blind-spot warning systems which are built in many newer cars. Those cars often use weak K-band radar to "see" other vehicles nearby. The new V1 automatically rejects those.

2017 C300
 

Had the Audio head unit center screen do this lock up on my 16 Maybach and the 18 GTC. A reset solved the problem. Also on the GTC the cruise control stopped working with a message similar to your screen. I simply turned car off and restarted and all is well.

I suspect these cars simply occasionally need the CTL ALT Delete reset.

Has anybody found an actual solution to this problem? 🤔

I believe a lot of different issues can cause this error code so the solution is rarely the same for two cars. For my car, I had this code and it was caused by an improperly adjusted brake switch.

I experienced this issue when pulling out of the warm garage into cold air. Was determined to be condensation that quickly developed between the sensor and plastics. Would cause the signal to bounce I suppose. I rarely drive it below freezing, but I found letting it sit for a couple minutes outside before driving did the trick for me. No problems since. Simple restart would clear the limp mode before doing this method.

I had the same problem with my 2016 GTS, only thing that would make the warning go away was a key cycle. Luckily when i took it to the dealer they saw the code and said "module under dash" needed replacing, which took a week to get. So far no more warnings. That warning is annoying as you cant clear it.

By any chance do you happen to have the part number of that module?

Man it drives me nuts this message. It started happening on a rainy day. So I don't know if the sensors picked up water, or the radar sensors are faulty. But so far what I have researched like you said there is a couple things that could be but nothing definitive.

I dont I am sorry, I would call my SA but he is off until the 4th.
I didnt get the repair order as I was in a hurry to get it out of there that day due to weather coming in.

One thing the mechanic checked when i first brough it in for it (didnt drop it off then) is he checked to make sure the cameras werent blocked by something, they are by the rear view mirror from the outside of the windscreen.