Sensors and Lead Wires

Fig. 18 ECM sensor circuit test connections:

Fig. 19 ECM sensor circuit test specifications:

The feedback system uses the following sensors: wide open micro switch, idle micro switch, thermal switch, high altitude compensator, thermal engine compartment switch and fifth switch. If any of these sensors malfunction or if a sensor circuit is interrupted, the feed back system will not function properly since the ECM is not receiving a signal. Check each sensor and its circuit as follows:
1. Turn ignition off.
2. Disconnect ECM connector.
3. Connect ohmmeter between terminal 4 of ECM harness connector and terminal 1 (ground), Fig. 18, and measure resistance. Repeat with terminals 5, 11, 14, 15 and 19.
4. Compare observed reading to Fig. 19.
5. Reconnect ECM connector securely.