Inspection of PCM and Its Circuit

INSPECTION OF ECM AND ITS CIRCUITS








ECM and its circuits can be checked at ECM wiring couplers by measuring voltage and resistance.

CAUTION: ECM cannot be checked by itself. It is strictly prohibited to connect voltmeter or ohmmeter to ECM with couplers disconnected from it.

VOLTAGE CHECK
1) Remove ECM from body.
2) Connect ECM couplers to ECM.
3) Check voltage at each terminal of couplers connected.











NOTE: As each terminal voltage is affected by the battery voltage, confirm that it is 11V or more when ignition switch is ON.





RESISTANCE CHECK
1) Disconnect ECM couplers from ECM with ignition switch OFF.

CAUTION: Never touch terminals of ECM itself or connect voltmeter or ohmmeter.








2) Check resistance between each pair of terminals of disconnected couplers as listed in the above table.

CAUTION:
- Be sure to connect ohmmeter probe from wire harness side of coupler.
- Be sure to turn OFF ignition switch for this check.
- Resistance in table represents that when parts temperature is 20°C (68°F).