Hello there:
The machine: 2000 528i--- It looks like a bad pump, but I was wondering if there was a sure shot test to confirm that it is the pump and not a relay or something else, I might be missing. I am just confused because as per other forum threads we would expect to see a broken valve which flooded the pump. Here the valves are clean and dry, free of carbon and dirt. Also, I checked for voltage and it gives 2.5 volts at the harness and it shows continuity at the pump. Is this too low, or am I placing the multimeter probes in the wrong place.
2.) Is there a way to see if the valve is functional if the pump does not work?
3.)Interestingly, there are five relays in the trunk and the one in the right side in the extreme rear seemed to be bad. Is this the relay in regard to the pump?
I was also wondering if anyone had a electrical circuit diagram for the pump or the relay that I could trace for defects. Any suggestions really appreciated. I hope someone might have tackled this challenge before.