ECM Power Circuits

Fig. 17 ECM power circuit test connections:

The ignition coil, solenoids and solenoid valves are all connected to the ECM. A loose or open connection in any of these circuits will cause a loss of signal to the ECM, thus causing the system to malfunction. Check all power circuits as follows:
1. Disconnect ECM connector.
2. Turn ignition on without starting engine.
3. Connect voltmeter between terminal 2 of ECM connector and body, Fig. 17, and measure voltage. Voltage should be 12 volts. Repeat with terminals 3, 8, 9, 12, 13, 16, and 18.
4. Measured voltage should be 12 volts. If not check wiring.
5. Reconnect ECM connector securely.