Fast idle contoller
 

My 1986 500sl euro has developed a fast idle. It will not idle at 500 to 600 rpm. The idle control motor has no voltage. My problem is I cannot locate the idle control unit !!! I have checked both sides under dash and passenger footwell. This is my first time I have been stumped with this car. I have owned it since 1990. Love the power... Vic

Idler Control Unit
 

Vic,

The idle control unit it is located under the cover on the passenger footwell stuck high up on the left (as per photo item 21). Before testing the unit suggest to check and replace the OVP fuse under the cover of the box also under the same cover up the fuses racks.

Thank you for your reply. I have removed that cover and my car is not arranged as the photo!!! I have checked ovp fuse, not burn't...I have removed all 12 pin connectors and ran part numbers,on each box....None have been idle controller!!! I have not removed glove box, should that be necessary?