I have two orange warning lights on the dash- BAS ESP and ETS. Things are running fine? 2001 320ML

Check relays

Brake light switch problem may cause the ESP / BAS lights to illuminate.

Common symptoms of a bad
Mercedes brake light switch.

• Car stuck in Park.
• ABS ESP ETS lights come on.
• Can not move the shifter from Park to Drive.
• Brakes Defective Warning on Instrument Cluster
• Car won't shift gears. Stuck in 2nd gear, limp mode.
• Brake lights don't work. (Brake light switch can still be defective even if the brake lights work. Checking the brake light operation is not a good test.)
• ESP, BAS, ABS lights turn on. Car won't shift properly. Stuck in gear.

TEST: To test your new brake light switch: Turn you car off to reset the ABS light. apply the parking brake. and start the car in neutral or park without using the brake. if the problem is the brake light switch... the light will only come on when you press the brake pedal.

If you replaced the brake light switch and the light is still on you should check a few other things such as:

• Fuses and Relays
• ABS pump
• ABS wheel speed sensor
• Brake Fluid Level
• Get an advanced scanner to read trouble codes.

NOTE: ** You may need a MBZ scan tool to reset the error code which was stored in the ECU because of the bad brake light switch.

Whenever this warning or any other stays on in the dash it id indicating that the systems control module has detected a fault, it then disables the system as long as the light is on. You must now have the dealer hook up a special electronic diagnostic tool and "scan" the system for the fault code that is stored for the problem(s)

Hi there:
The BAS/ESP lights pertain to your brake assist and electronic stability systems. One of the more common problems we find is a faulty stop light switch or a steering angle sensor. It would be a good idea to have the fault codes read. The codes would give you a pretty good idea as to what is going on. You could try to initialize the steering angle sensor first. This is normally needed after a dead or weak battery condition. To do this you'll need to start the car and then turn the wheel slowly all the way to the left, pause and then turn slowly all the way to the right, pause and return to center. You may need to do it a couple of times to initialize the sensor. The stop light switches are inexpensive and easily replaced. They're located under the dash at the brake pedal. When you get your new switch you'll see a little release tab on it. You just depress the tab and rotate the switch 90 degrees to remove it.


Before to replace some parts, I suggest scaned the computer car in order to know other fault codes stored.

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The BAS stands for Brake Assist System, don't remember what ESP stands for.
But the first thing to do is make sure the brake lights go on when you hit the pedal.
If not, then replace the brake light switch above the pedal.
If that is not it, it could be many things, such as a bad lateral acceleration switch.

the bas warning light is on along with the ets warning light, how to I repair the problem? The code reader indicates that it a sppeed sensor.

ESP = Electronic Stability Program
BAS = Brake Assist System

http://jeephorizons.com/phpbb/viewtopic.php?t=6836

Yes it could be that simple and probably is.

Hi,

To my understanding:
BAS ESP - Electronic Stability Program (keeps you moving in the direction you intended the vehicle to go); probably a faulty brake switch or a bad brake sensor. You may want to reference this forum for additional insights;
ETS - Electronic Traction System (keeps you moving); would require an appropriate code reader to diagnose and pinpoint problem.Surprisingly, there has been some reports of defective brake pedal switch that activates this warning. You may lilkewise want to reference this forum for additional insights.

Hope this be of initial help/idea. Pls post back how things turned up or should you need additional information.

Good luck and kind regards.

Thank you for using FixYa.