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Discussion Starter #1
Does anyone know if there is a way to test the idle control unit to make sure that it is not working properly. I want to avoid spending the bucks for unit if this is not the problem for sure. This is a '82 380 SL.<br> <br> Thanks<br> Ray
 

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Ray,<br> <br> Detach connector at control unit, (the connector has 12 contacts) switch on ignition, test whether battery voltage exist at contact 2 (positive) and contact 4 (ground). If not voltage exists:- a) test black/red cable between contact 2 and fuse 14 (terminal 15), b) test brown cable, contact 4, to ground (refer to wiring diagram).<br> <br> If voltage exists:- Briefly jumper contacts 1 and 2 and 4 and 5 simultaneously (max 5 seconds), idle speed adjuster must be heard to switch. If idle speed adjuster switches, check contour hoses for passage, if ok renew control unit.<br> If idle speed adjuster does not switch, test cables (contacts 1 and 5) between idle speed adjuster and control unit for continuity, if resistance is not approx 0 omg rectify cabl interrupt according to diagram. If resistan is approx 6 omg check green/yellow TD cable from fuel pump relay to control unit for continuity, if resistance is not 0 omg rectify cable interrupt as per wiring diagram. If it is 0 omg <br> check additional functions by testing cut-in signal of automatic transmission and air conditioning compressor.<br> <br> Further tests:-<br> Engine idling at approx 80ºC oil temperature, engage drive position, if idle speed drops to 500 rpm this test is ok. If idle speed does not drop: switch engine off, switch on ignition, detach connector at control unit and connect voltmeter between contacts 8 (negative) and 2 (positive). Battery voltage must exist in position 'P' or 'N'. In drive position contact 8 (negative) is interrupted via starter lockout and backup light switch. If there is voltage renew control unit, if not test cable from control unit to ignition starter switch.<br> <br> There are further tests to be carried out if all above proves negative, including the idle speed adjuster itself.<br> <br> <br>
 

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Discussion Starter #4
If idling @ 2000 RPM, look for a relay above the fuse panel that has afuse on it. a 10a GM fuse will work. Start with that and I hope I saved you 3 hours work.
 
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