I can confirm the passenger seat sensor is a non-latching fault type of SRS error. My 99 E320 Wagon has a bad seat sensor that will trip the SRS warning light if someone over 200 lbs is in the passenger seat. Once the exit the seat of if they're replaced by a lighter passenger the light immediately goes out. I've read the code with an SDS machine and when the light is on the code for passenger seat sensor is present. The 36 pin interface is the only way I've been able to get in touch with the SRS system.

I'm 99% sure its just a broken/frayed wire but I haven't bothered to fix it.

I'm also pretty sure that the original poster has some sort of SRS problem and I'd bet its the front passenger seat sensor.

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