German Car Zone

Hi Guys,


This morning, my girlfriend tried to took off with her A150 W169 (Autotronic, Avantgarde, Nov-2005). The engine started up well, but she couldn't move the gearstick from P. A couple of seconds later 3 error messages came up from nowhere:

- Brake lamp, drive to workshop
- ESP faulty, visit workshop
- Run flat indicator not available

We've checked, and all 3 brake lamps worked fine, and all tyres were OK as well. After trying 3-4 times to move the gear lever, finally it gave in, and we could start the trip. After a couple of blocks, we realized:

- the steering got a lot heavier
- we cannot accelerate above 55 km/h

We've stopped, turned the engine off, and checked all fuses related to ESP. They were all OK, started the engine, and everything seemed to be back normal. Steering was fine, acceleration and speed was fine.

Then at the next stop the gear lever stuck back in P again, and the 3 error messages, the heavy steering and the 55 km/h limitation came back. We headed home. After we arrived home, I've tried to power off the engine and power on again, and the error messages were gone again.

I'm now afraid of leaving home with this car, so the next trip will be to the mechanic's. Do you have any idea what could be wrong? Maybe the TPS (Throttle Position Sensor), or the brake pedal?

BTW, the car has 68.000 kms, and we had no issues with it before.


Thanks,
Fiery

Sounds like an electronic glitch.

Better to contact your local Mercedes dealer and have them do a full analysis. The new W169 A-Class has generally gotten great reliability reports but things can always go wrong.

Also have them check brake fluid, power-steering fluid etc., just to be on the safe side.


Or contact this man: Ralph Mietzner

ralph.mietzner@gmx.net

He is an A-Class expert and can help you. Tell him that I (Christian Wimmer) gave you his contact details.

Best of luck!

Thank you, I've dropped a message to Ralph. We'll take the car to a full analysis tomorrow or the next day. We love this car, so I hope there's only a small glitch that could be fixed in a reasonable budget

You mentioned that the car does not accelerate over 55km/h. You mean that the car won't switch to second gear, or that no matter the gear that is in, the car just won't go faster than that?

It's a CVT gearbox, so there are no gears The 55 km/h limitation is simply a speed limitation, probably they call it "safely get home" feature. Even if you floor the accelerator pedal, the car wouldn't change its speed at all.

No problem.


By the way, that 55 km/h speed limit might be an electronic safety precaution, which then means there is something very wrong with thecar.

A stupid question, but did you fill it up with the correct octane of gasoline?

Yeah, that part is quite normal considering an ESP failure. However, what I don't get is why does everything goes away (no errors, no 55 km/h limit) after powering off and then powering on again? Maybe there's a wrong sensor somewhere, and it reports a failure at ignition self-check -- but not on every ignitions. Once the car started with no errors, we drove 30 kms without a glitch. Then after the stop, at ignition the errors and the limit came back...

A relevant question, but we filled it up with the usual 95-octane unleaded, at the usual filling station -- just like several times before. After the full fillup my girlfriend drove cca. 200 kms without issues, and the error came up when it was half a tank. So I don't think the gas had any issues.

Thanks for the brainstorming, please keep it up, the tips may come useful if the computer analysis cannot point to a specific faulty part.

Well that is the problem right there!



Wow after 12 years I finally made it to 1,000 posts!!!!

Lol I didn't know you were a mechanic

and Congratulation on the 1000 posts

What where have you been? Yes I was a Mercedes tech, I spent 4.5 years at two different Mercedes dealerships.

Didn't work on any A or B class cars though