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Part 1

Inspection of ECM and Its Circuits

ECM and its circuits can be checked by measuring voltage, pulse signal and resistance with special tool connected.

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

Voltage Check
1. Remove ECM (1) from its bracket referring to Engine Control Module (ECM) Removal and Installation.
2. Connect special tool (A) between ECM and ECM connectors securely.
3. Check voltage and/or pulse signal using voltmeter (2) and oscilloscope (3).

NOTE:





- As each terminal voltage is affected by battery voltage, confirm that it is 11 V or more when ignition switch is turned ON.
- Voltage with asterisk (*) cannot be measured with voltmeter because it is pulse signal. Use oscilloscope for its check if necessary.
- Before performed this inspection, be sure to read the Precautions of ECM Circuit Inspection.







ECM Connector "C37" (Part 1):




ECM Connector "C37" (Part 2):




ECM Connector "C37" (Part 3):




ECM Connector "C37" (Part 4):




ECM Connector "C37" (Part 5):




ECM Connector "C37" (Part 6):




ECM Connector "C37" (Part 7):




ECM connector " C37 "

ECM Connector "C23" (Part 1):




ECM Connector "C23" (Part 2):




ECM Connector "C23" (Part 3):




ECM connector " E23 "

Reference Waveform No.1:







Reference waveform No.1

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Reference waveform No.14