Won't Start...Then Magically Did
 

Hi folks. I've got a 2022 GLS 450 X167. Drove it twice this AM for a few miles. Then parked it at the store for about an hour. Got in, pushed the START button and the dash lit up like normal, but the engine didn't turn over. Nuthin'. Tried several times with the same result. Checked battery voltage - 11.8V, so that was not the problem.

I called my guy at the Dealership, and he told me to close the car, lock it, take away all Keyless-Go keys - just let it go fully to sleep for 15 minutes - and then try again. Did all this and let the car rest for 30 minutes, and bingo, it started right up.

My dealer said I needed an update of some type and that this was some sort of Keyless-Go issue.

Has anyone else had this problem? More than once? What's the root cause issue, and were you able to get it fixed?

Thanks for any info/advice.

I've had this happen. I've also had it happen when I was sitting in the GLS in carpool line and it had shut off (auto start stop). When the line started moving, I couldn't shift into gear and I tried any number of things, but it wouldn't start. While waiting for the wrecker I had left it alone for about 15 minutes. I tried one more time and it started. I drove it to the dealer and was told they couldn't duplicate it so it's fine. I have a thread on here about it.

The one common thing I had was it always gave me the messages "Press brake to start" or "Press brake to shift into gear" even though I was firmly pressing the brake pedal. I believe it is something faulty with the brake pedal or that circuit. It is very aggravating. Both time's I have blocked the line of parents trying to pick their kids up from school and the police had to come direct traffic around. Mercedes attitude was basically "We can't get it to do it so it must be you" I need to take it back since it has happened again. I have been hoping to duplicate it again so I can video the event and thus nullifying their bs attitude about it.

Thanks. I'll try to find out some detail on what my dealer updates e next week and pass it along to you so that perhaps your dealer can help you.

LeadfootCJ7 - don't know your location in H-Town, but if no luck at your dealership consider contacting MBoTW and speak with the Service Mgr-Anthony. I've had excellent service there. Steve

I might end up taking that route. I live on the westside and that would be a solid 40 minute drive without traffic. They were recommended by the dealer that sold my GLS new and did all of the service work for the 18 months prior to me purchasing it. They are apparently under the same ownership and told me they work together (although I'm curious how the service departments many states apart would work together). Ideally, I would like one of the 2 dealerships nearest me to be able to solve this.

Well, after taking my GLS 450 in after not starting, my dealer put a new 48V battery in it. There are also apparently software updates to try to solve this no start issue, but none were listed for my particular vehicle. So, I hope that the new battery does the trick and that my problems are over.

Thanks for updating the thread.

MB and 48V batteries are an unfortunate pair. They have struggled unsuccessfully for 4 model years to get this system right. And yet have failed to do so.

The GLS is a nice car, shame the MB shoddy engineering can’t be trusted.

Fingers crossed as I'm driving it to Alaska in a few weeks!

I dropped my GLS off today at the same dealer as last time to address this problem and a few other issues. They had a different attitude. Apparently they have another Mercedes (I believe GLS, but can't recall if they said specifically) with the same issue and have an open case with Mercedes for this issue. It is unresolved currently, but they are aware of it and are now aware Mercedes has this problem with more vehicles rather than it being an isolate case. I'm hopeful they can find a solution, but I am pleased they are taking it more seriously this time. It seems like they are leaving it up to Mercedes to give direction on repairs for this issue.

I picked it up today. I was told they tested the brake pedal and found the brake pedal intermittently didn't send the signal for the vehicle to start. There is a new brake pedal assembly in it. The story I was told in chatting with the advisor seemed a little different and I get the feeling the technician might have just replaced it since I have had the problem multiple times and it always gave me that error message. I am hopeful that it fixes it, but I'll wait to see.

Any updates on the root cause of this issue? I've had it happen to me twice this week and want to go to the dealer but I know they will just say its working fine when they can't reproduce it.

Mine has not acted up again since the new brake pedal assembly or sensor. I assume that was the problem based on this event no longer taking place.

Was there any internal TSB that you are aware of? If something like this is very common, there must be some form of a bulletin available for it. Was it the brake pedal assembly or "sensor"? and was that an arbitrary solution by the tech?

I hope there is a TSB for this I can reference. I made an appointment today to take it in and I'm sure they will say it's working fine and send me on my way.

Thanks for the response and good luck today. Keep us posted. The reason I asked about TSB, if you find one, it's help you to force them perform a certain repair when symptoms are exactly matching what's their in the TSB. Don't expect the SA to know all TSBs.