Ironically, I was driving my 2000 ML320 to have brake rotors and pads replaced, and intermittent BAS / ESP light flashing, when all ^&* broke loose. The triangular yellow traction control light started flashing in unison with the brakes engaging by themselves. I slowed down quite a bit and while making a slight turn the brakes locked up. Pulled over 1/2 mile from the repair shop, turned off the ignition and made a call. The problem went away.

Had the brakes done, and the BAS / ESP problem is apparently a steering angle sensor which can be reset. The theory is that the sensor caused the traction control to kick in. Does this make sense, and would it be safe to drive until the sensor is replaced?

Thanks in advance

 

It makes a lot of sense. The steering angle sensor reads the amount of steering which the car is involved in. For instance, if the sensor is faulty, and it gives the ESP control module the wrong information, it could cause the control module to think that you are in a hard turn when you are actually not. It can conflict what other information the vehicle is getting from yaw rate, lateral acceleration and the wheel speed sensors. most likely, you won't be able to reset it. If it is failing, it must be replaced and unfortunately on that model(ML) it is part of the steering column! (The reason why you heard it canbe reset is because usually if the battery is disconnected, the sensor has to be recalibrated. You will get a warning for ESP/BAS, and if you turn the steering wheel lock to lock a few times, it will go away. But in your case, if it happens while driving, the sensor is probably failing.

 

Not 100% convinced although feasible.

Concerned regarding potential failure Mode. Clarification sort as to whether the system applied brakes at high speed or just as you were turning off the highway (much lower speed) to determine why the Yellow triangle light had come on?

Surprised that MBZEX didn't suggest getting an MB Star Quick test done to see what (if anything) the On Board Diagnostics thinks is wrong.

Been raining recently?

What made you book in for new pads and rotors. Did you have the wheels off immediately prior to the problem?

Vehicle history. mileage etc?

IMHO Most likely cause.

Steering column sensor Normalisation (Carry out alibration Turn lock to lock)
Lack of wiring integrity. broken wire, short including plug corrosion.
Speed sensor fault including rotor dust. Clean check resistance.
Steering column sensor fault.

Hope this helps.

Suggest you don't drive again until the problem is resolved or at least till after the Quick Test.

Stuart

 

The brakes only locked at low speed. There was a fault with the Steering Angle Sensor when the diagnostics were hooked up, but it could not be reset. I hate to go for the new sensor if it's a wiring problem.

Any chance that a bad brake switch could show up as a SAS fault?

 

me too! what caused this? i know this is a very old thread.
bought a 2000 ml320 a week ago. yep all 3 lights on. did some research, made sure all brake lights worked, swapped relays in main fuse block, bingo k25!!
so now a new problem arises (go figure) this is what it does now:

while driving the yellow triangle in the speedo starts to flash, this is followed by the car acting like it is about to stall out (whole thing feels like a front tire has blown) with noises coming from the front. without doing anything but praying the car doesn't die, the engine powers back up and drives normal again only now the ets/bas light stays on, the other 2 never come on. when i get back in the car to drive again no ets/bas light until at any given moment the above happens. i don't think it is the brake light switch or the abs light would be on, right? not cutting the steering wheel hard, so shouldn't be sensor there? do i need to disconnect the battery and reset the computers? previous onwers took exceptional care of the vehicle other that driving it with the "3 yellow lights" on for 3 years! really!? Anybody else had this problem and can point me in the right direction, thanks