KSGlock

I am getting an SOS Inoperative light on the dash. I am unable to reset it and the dealer is basically useless. Has anybody dealt with this issue before??

karmikan

You're going to have to be a bit less sketchy with your info. Model/year, what did the dealer tell you/do/not do, what are your symptoms if any? etc etc...
Your dealer being "useless" isn't much to go on.

KSGlock

2014 GLK 350. 4Matic. The dealer advised they would only replace the tele module. They claimed they had not seen it before. I don’t feel they know what they are talking about. I don’t want to throw parts at it either.

karmikan

Usual dealer approach - throw parts at the problem and hope for the best.
If you have a warning light you probably have a fault code which you can read to pinpoint the issue. If you have a code reader you could do this yourself. If not try a reputable indy with the necessary MB diagnostic expertise. Do you have any symptoms or is it just the warning light?

KSGlock

It doesn’t throw a code. It only pops up on every start up of the engine. Just pops up as a SOS Inoperative. I don’t have a shop around here aside from the dealer. I called one that was about an hour away that wanted me to leave the car and he would fit it in. They thought it would be a week plus. I didn’t want to take that route.

karmikan

Found this potential fix. Can't confirm it works but worth a try.

To turn off the SOS warning, shut off the engine and then turn the key back on. Then turn on the headlights and leave them on for two minutes. Then turn them off and turn off the key. The message may still there at the time but will be gone the next morning. It has to do with the brain box having a battery voltage question and by burning the headlights for two minutes, the brain box sees a voltage drop and records the new battery voltage.

KSGlock

So I tried the above and it didn’t fix the issue. I put a battery tender on the main battery and it took a long time to get to the maintain only spot. After running the vehicle. It goes right back to needing a lot of charge. I’m thinking it is the battery going bad. Maybe both? I’m not sure what runs what.

Mmr1

I’ll bet your battery is original and weak, weak batteries cause a lot of problems even damage to electronics. Get it tested and probably replaced. If it’s original and as you said was hard to charge just replace it with a AGM battery. Most all auto parts stores test for free and some instal, I just replaced mine.

Mmr1

Your car has two batteries if you have auto stop start, what is SOS system? Auto Stop start ?

KSGlock

Both batteries are AGM. So I will look into replacing those. Is there a brand people prefer?

it shows SOS Inoperative and the telephone symbol. And all the lights on the ceiling are lite up. The SOS, emergency, and call light.

I think the batteries are bad. I’ll get them out and tested ASAP.

rbarnard

what happens if you dont have a key. mine is 2018 model with the digital display

habbyguy

You start by going to the right forum (either it's a different 2018 model, or it's a GLK that's not a 2018).

MB2timer

I had the problem, talked about it on another SOS inop thread.
The dealer loaded the most current software update, and it has reduced the incidence to a minimum.
I found in another thread, that others had the issue, and it was moisture related.
Some moisture around the headlight cases. That was resolve by having the headlights on for 2 minutes without the engine running.
The other problem area was in the trunk where moisture was getting into some electrical connections.

mogulman

I had this issue. When it happened, I thought it was the module that calls out, using old 3g tech that is no longer available on any US cell networks. I lived with it a while.
Then I brought the car to a local independent mercedes shop. I was going to have them disconnect the module, so the message didn't come up any more. They said they didn't need to do that. They just cleared the codes in the system and the message went away. Hasn't come back in a year of driving.

This is for a GLK. Your car is different so probably should post in a different forum

Mmr1

Can you locate your car through the Mercedes Me app? . My 13 has no more cell service because MB is to dam cheap to keep it going .

calder-cay

This is really OLD NEWS. It's a hardware issue, and is related to cellular network providers, NOT MB.

quote: ****Major U.S. network providers**** plan to decommission their 3G networks in **2022**".
This will affect your Mercedes-Benz mbrace services if your vehicle is 2016 and prior and select 2017 models.

https://www.mbusa.com/en/owners/3g-network-sunset

Mmr1

Yea and we can PAY to have it continued on a different system .