ECM Branch Line Circuit Check

ECM Branch Line Circuit Check

1. CHECK CONNECTOR

1 Turn the ignition switch OFF.
2 Disconnect the battery cable from the negative terminal.
3 Check the following terminals and connectors for damage, bend and loose connection (unit side and connector side).
- M/T models
- ECM
- Harness connector E152
- Harness connector M31
- A/T models
- ECM
- Harness connector E2
- Harness connector F32

Is the inspection result normal?
YES
GO TO 2.
NO
Repair the terminal and connector.

2. CHECK HARNESS FOR OPEN CIRCUIT

1 Disconnect the connector of ECM.
2 Check the resistance between the ECM harness connector terminals.
- QR engine models






- VQ engine models






Is the measurement value within the specification?
YES
GO TO 3.
NO
Repair the ECM branch line.

3. CHECK POWER SUPPLY AND GROUND CIRCUIT

Check the power supply and the ground circuit of the ECM. Refer to the following.
- QR25DE: [Power Supply and Ground Circuit Check] Power Supply and Ground Circuit Check
- VQ40DE: [Power Supply and Ground Circuit Check] Power Supply and Ground Circuit Check

Is the inspection result normal?
YES (Present error)
Replace the ECM. Refer to the following.

- QR25DE: [Procedure After Replacing ECM] Testing and Inspection
- VQ40DE: [Procedure After Replacing ECM] Testing and Inspection
YES (Past error)
Error was detected in the ECM branch line.
NO
ERROR! Unknown action!Repair the power supply and the ground circuit.