Operation CHARM: Car repair manuals for everyone.

Engine Temperature Switch Test

Fig. 6 6 cylinder electronic spark advance switches and sensors. Front view:




Fig. 7 6 cylinder electronic spark advance switches and sensors. Rear view:






Turn ignition ``Off.'' To test temperature switch, connect a suitable ohmmeter between center terminal of temperature switch and ground. To test charge temperature switch, connect ohmmeter to center terminal of charge temperature switch and switch ground terminal.
With engine cold, continuity should be present with resistance less than 100 ohms. If not, replace switch. Charge temperature switch must be cooler than 60° F in order to perform test properly.
With engine hot, continuity should not be present. If continuity is present, replace temperature switch.