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View Full Version : 90 535i ICM / ICV electrical questions



wjbell
03-30-2007, 06:09 PM
I was reading an idle FAQ for older 325's and decided to check some stuff on mine with a volt/ohms meter.

There are three pins to the ICV. When I pull the plug and check ohms on the ICV itself I get 43 ohms from the two outside pins and about 21 ohms from the center pin and either outside pin.

Checking voltage on the connector side I get 8-10 volts if I have the positive in the middle and the negative on either side. If you're looking into the plug connector (coming from the ICM) and you have the negative far left and the positive far right I get about 5 volts. But strange thing is, when I first turned the ignition to full run position (without starting the car) and put the meter on it it started off at about 3 volts and slowly climbed to 5.

Another thing, if the ICV is plugged in and I start the car, then pull the connector, nothing happens. No idle change whatsoever. But if I have the ICV unplugged, start the car and let it idle (it idles as usual when I do this) then plug the ICV in, the car almost dies then revs up to about 1500-2000 RPM and returns to normal.

From any of this can anyone tell if either the ICV or ICM are working properly or not?

What concerns me is the slowly rising voltage from the two outside pins and the fact that there is no change in the idle when pulling the plug to the ICV.

TIA