FYI. Check engine light appeared on my 2008 E350 (W211). No errors appeared in the instrument cluster display. Using an OBD reader, multiple error codes detected. I erased all codes and checked again. There was a fault in the REAR SAM-Rear signal acquisition and actuation module. Fault code was 9092 Communication fault with the component 'Battery sensor' (2).

Error code 9092 is usually associated with the auxiliary battery, however; this car does not have an auxiliary battery.

I replaced the main battery in the trunk and the error code cleared. The existing battery was approximately 8 years old, however; the battery did not show any signs of dying - car always started normally. Interesting way to determine that the battery was beginning to fail.

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1995 E300D

Getting 8 years out of a battery these days is real good. What kind of battery was it?

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Jim

The battery was a NAPA Legend Premium AGM Technology Part No. 9849. The car isn't driven hard with only about 55,000 miles on it.

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1995 E300D