Hi, I have bought a Merc A-class as a non-runner as i work at a garage. The problem with the car is that the words 'start error' are displayed when the ignition is turned on and the car will not crank at all. I dont know the full story with this car but the car was stood for a good year in which the battery went flat, whether the car was like this before i do not know. I understand the W168 is very delicate on the electronics with regards to power spikes etc.
I took the car to a local dealer who did a few tests and, in my view, gave up and pointed at the ECU being at fault. This may be the case but i am just exploring other possibilities before i take the plunge. I have gained access to the immobiliser system under the O/S dash trim which had the oddest aftermarket system attatched to it. The system was routed through this aftermarket system which was then routed into the back of the speedo clocks and back, then into the original alarm sytem etc etc. I took all of this system off and replaced all the connectors to their original location i.e in the speedo and 'homogalation' box. Still no joy with the car and removing all of this hasnt changed anything, the key still operates the alarm etc.
I have done some investigative work at the start relay and everything is there except the power on the brown/red wire is not switching to earth as it should to activate the starter. When i feed an earth in to the relay the car will crank but not start so presuming pump etc is immobilised. I do read another post on here that talked of the same problem, cured by resetting the ECU with a star machine. I was going to look at the key next, wondering if it has lost its code or something?
If anyone could be of any help with this problem it would be greatly appreciated. Also does anyone know of a way to bypass the ECU just to get the car running?
Thanks in advance
David
I took the car to a local dealer who did a few tests and, in my view, gave up and pointed at the ECU being at fault. This may be the case but i am just exploring other possibilities before i take the plunge. I have gained access to the immobiliser system under the O/S dash trim which had the oddest aftermarket system attatched to it. The system was routed through this aftermarket system which was then routed into the back of the speedo clocks and back, then into the original alarm sytem etc etc. I took all of this system off and replaced all the connectors to their original location i.e in the speedo and 'homogalation' box. Still no joy with the car and removing all of this hasnt changed anything, the key still operates the alarm etc.
I have done some investigative work at the start relay and everything is there except the power on the brown/red wire is not switching to earth as it should to activate the starter. When i feed an earth in to the relay the car will crank but not start so presuming pump etc is immobilised. I do read another post on here that talked of the same problem, cured by resetting the ECU with a star machine. I was going to look at the key next, wondering if it has lost its code or something?
If anyone could be of any help with this problem it would be greatly appreciated. Also does anyone know of a way to bypass the ECU just to get the car running?
Thanks in advance
David
