If I'm testing properly...
I have a 83 500sl thats idling at about 1500-1600rpm. I'm using the testing from the Service manual CD.
Disconnecting or reconnecting the connector onto the idle control valve causes no change in idle speed.
With a multimeter I'm reading approx. 13 volts from the connector that plugs into the idle control valve. If I push the connector part of the way on the idle control valve and try to get a reading by connecting the multimeter to the still exposed portion of the idle control valve I get nothing. If this is the correct way to test this the manual says I should be reading 5v +/- 1.
Am I understanding the testing procedure in where I am trying to read the 5v?
If I apply battery voltage to the idle control valve the idle drops to approx. 500rpm.
If this is correct, then it appears I have a defective idle control unit.
I have previously removed this unit from the car to look for broken solder joints, didn' find any but, resoldered around the connectors as I read this was a common weakness.
Are there any parts forward of the idle control unit that could cause the idle control unit to appear defective?
Any thoughts or suggestions would be appreciated.
1983' SL500 euro