I have had a fault with ASD light on. I was advised to check the overvolt relay fuse and it was blown . Now Ive replaced it the but light is still on. Does this have to be reset electronically ,if so, how can I do it myself?
The car is a 300CE 24v w124

IF there is a fault(code) in the system it must be scanned & the fault must be repaired. Then the code can be erased.

I understand this but how can I reset the fault code without going to the expense of booking the car into a main dealer .Can you for example disconnect the battery for several hour s or short out pins on the diagnostic connector etc.
This is an old system so ther must be some volatility in the fault memory . How is this backed up , a lithium cell? capacitor? or perhaps a relay is latched.