1995 E320 wagon.
I will try to organize what I have tested thus far please bear with me:
The air injection pump does not come on.
It is supplied power from the main computer along with the switchover valve. The pump does come on when jumped with 12v from the battery.
There does seem to be continuity to the main computer (the wiring harness is not bad)
The resistance of the electromagnetic clutch of the pump is ~3-4ohms
The Voltage at the pump connector (on cold start) is ~6v only when the swithover valve or ground location is disconnected!. Otherwise it is low (mv).
Questions: is 6v the pump supply voltage, could the switchover valve short the pump, could this be due to incorrect wiring of the new harness - any knowledgeable feedback would be appreciated!
thank You