Operation CHARM: Car repair manuals for everyone.

Coolant Temperature Sensor/Switch (For Computer): Testing and Inspection


1. With ignition Off, disconnect multiple pin plug from DME ECM.
2. With temperature sensor wire connector attached, connect suitable ohmmeter test leads across ECM connector terminal 13 and ground. Resistance should be as follows:
Resistance @ 0°C (32°F) 4.4K - 6.8K ohms
Resistance @ 15 - 30°C (59 - 86°F) 1.4K - 3.6K ohms
Resistance @ 40°C (104°F) 1.0K - 1.3K ohms
Resistance @ 80°C (176°F) 250 - 390 ohms
Resistance @ 100°C (212°F) 160 - 210 ohms
3. If measurements obtained are outside specifications, repeat test on temperature sensor to determine if problem lies with sensor or with wiring.