w220 s-class 280 brake lights staying on

[BillyW124]

Chaps,

A friend of mines has developed a fault on his s-class whereby when the ignition is turned off the rear and centre brake lights stay lit. The front lights stay off.

Brake light switch has been fiddled with and replaced - no joy.

Culprits like a short in the wiring have been checked and there isnt any chaffed wires or splits in the circuit.

Any ideas?

 

[BillyW124]

^^

 

[clk208]

Have any bulbs been recently replaced? Changed a brake bulb on mine for one that looked identical but must have differed slightly as it caused the rear lights to go haywire until swapped out.

 

[SilverSaloon]

doesnt the W220 have a system where if a brake light goes out, the reversing lights light up instead.

maybe something to do with that system. incorrect bulb wattage?

 

[mercedescl500]

I think either the brake switch is not seated absolutely correctly (try fiddling it again) or you have a rear SAM Module problem. (Rear SAM is under back seat). If you access to a scanner/star then it will be quick to get to the cause of the problem. Have you tried disconnecting the battery fully, for at least 1hr ? HTH