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Mercedes SRS Lite

The SRS light (air bag light) is constantly illuminated on my dash…it just decided one day to come on and stay on when the car is running. I took it into an import car repair center and they did a dignostic check and said it shows the SRS light is on b/c the car has been in a collision and the air bag has deployed…the car has never been in a colllision and the air bag has never deployed they told me it would require hours of work to figure out why the light is on …sounds like I’m being taken to the cleaners…any suggestions from anyone out there that might have had the same issue in the past? The Car is a 2002 SLK 230 with about 62,000 on it garage kept both at home and at work. Thanks.

Whether the air bag has ever deployed in the past or not, when that light is illuminated, it indicates that the air bag will not deploy in the event of a collision. So, I guess you have to decide whether it is a priority for you to have this protection in the event of a collision.

Diagnosing the problem could be time-consuming and could be beyond the scope of your mechanic’s skills, which could necessitate taking it to the Benz dealer. I would have it repaired, but the ultimate decision is up to you, of course.

I agree with VDCdriver. The Mercedes dealer is probably to place for this one, and it could cost a bundle. It’s up to you. Do you want the airbags to work or not. While you are deciding, make sure you ALWAYS fasten your seat belt, because it’s now the only thing between you and the windshield.

If the SRS light is steady on then there’s a physical problem with the system.

Your 2002 model uses the constantly connected spiral contact in lieu of the older contact ring and brush set up.

With the spiral design, the contact is a flat mylar cable that looks like a clock spring. When you turn left, it winds the spiral tight. When you turn right, it unwinds the spiral.There are so many turns on the spiral cable that even turning lock to lock puts only a small strain on the cable. The system seems to be much more robust than the older style contact ring/brush system.

However, any design will wear eventually.

If the spiral is cracked, or is receiving intermentant current the SRS light will come on and off. If this problem is not repaired in a timely fashion the control module will go bad, resulting in a steady on SRS light.

There is no “Reset” ability on the SRS light because the system is run indepentant of the CAN/bus computer system that runs most of the rest of the car. This is because the SRS system is a fundamental safety system that can’t afford to run on the comparatively fragile computer network to operate.

This is one of those jobs that should be seen by a Mercedes dealer. With luck, the spiral contact is cracked, or is not receiving sufficient current.

They will also check the piezoelectric accelerometer crash sensors and the interconnecting cables.

The final component is the control moduale itself.This will not be cheap to replace.

There are other defaults that will cause the SRS light to come on such as seat belt catches or even an alternator going out. But those symtoms are almost always an intermentant light, not steady.

Make an appointment soon to have this fixed.


The short answer. If the light is on, the airbags are disabled and will not function. Making the light go off will cost you a bundle. First, the problem must be found and repaired. Then, a new module must be installed. How much money are you willing to spend to make a light go off?

I had the same problem in a 1996 Toyota camry, After researching it I came ,up with 2 causes.

  1. The front crash sensor(s) may need replacing because of age or possibly being damaged by hitting or tapping something with the front bumper or someone backing up into you or even a deep pot hole.
  2. The air bag sensor wire which runs under passenger and driver side seat. make sure no wires are crimped or damaged from the seat track or from items shoved under seats. Do a search for SRS wiring diagram for you car to see what to check. Good luck

“10 YEARS LATER” . . . !

need I say more?


Elvis has left the building and I believe he took Jenfercoffee’s Mercedes with him, SRS light and all! :wink:

Next, please! :sunny:


You could say less, there is no need to bump old threads to the top.

Huh? :face_with_raised_eyebrow:
YOU just did! :wink:


No, it was still at the top because you bumped it.