E55K engine management light

[MOR8A]

Hiya. Just got into the car this afternoon and the engine management light has come on. The car seems to drive as normal. Any thoughts............other than telling me to get it code read on star? Thought I would dip my toe in the water here first.

Many thanks.

 

[ringway]

02 sensor, (4 of those) or failed cat, (4 of those if car is standard). Could be something else, though. It doesn't have to go on Star, pretty much any code reader will throw up the codes.

 

[whitenemesis]

Secondary air pump?

 

[Alps]

when i first got my car the secondary air pump caused the engine light to come on, local dealer wanted to replace the whole pump, but supplying dealer had the car recovered and replaced the relay and its bee fine since (over 3 years now)

 

[MOR8A]

Update: It was indeed the secondary air pump. Replaced the relay and had the code cleared down by Mercedes. Fingers crossed I wont be seeing it again. Thanks for your help chaps.