Operation CHARM: Car repair manuals for everyone.

Inspection of ECM and Its Circuits 3

Inspection of ECM and Its Circuits

31.Reference waveform No. 31




No. 4 ignition coil signal (2) at engine idling

32.Reference waveform No. 32




No. 1 ignition coil signal (2) at engine idling

33.Reference waveform No. 33




No. 2 ignition coil signal (2) at engine idling

34.Reference waveform No. 34




Engine torque signal to TCM

35.Reference waveform No. 35




Engine torque signal to TCM

36.Reference waveform No. 36




Manifold absolute pressure sensor signal (1) at engine racing

37.Reference waveform No. 37




Mass air flow sensor signal (1) at engine racing

Resistance Check
1. Disconnect ECM couplers (1) from ECM with ignition switch OFF.

CAUTION: Never touch terminals of ECM itself or connect voltmeter or ohmmeter (2).







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 the above table represents that when parts temperature is 20 degrees C (68 degrees F).