ECU A6121534279 from C270 CDI Blower circuit burnt out

[Colin Horsley]

The circuit that controls my main blower in the ECU burnt out. The fan remains on full speed constantly. The vehicle only has 58000km on it. After replacing the Main Blower (on the radiator) it was discovered that the problem was not the blower but infact the ECU. I opened the ECU and found one of the tracks to be burnt. Can this be repaired and why did this happen.
Regards

 

[television]

Hi Colin and welcome, re repairing the ECU, yes tracks can be repaired, and some components can be tested but not all.

The process involves checking the components on the output side of the ECU, checking that no components are S/C if all clear then the tracks can be repaired, I have done a few thousand during my life.

Its a matter of looking at the circuit diagram to see what other components its driving