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Component Tests and General Diagnostics

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 coupler disconnected from it.

Voltage Check:

Description:





- Remove ECM from body.
- Check voltage at each terminal of couplers connected.

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

Description:





ECM TERMINAL PINOUT











NORMAL VOLTAGE VALUES

Resistance Check:





- Disconnect ECM couplers from ECM with ignition switch OFF.

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

- Check resistance between each terminal of couplers disconnected.

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 below represents that when parts temperature is 20°C (68°F).








NORMAL RESISTANCE VALUES