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Engine Speed Signal Circuit




ENGINE SPEED SIGNAL CIRCUIT

Diagnosis Procedure


1. PERFORM ECM SELF-DIAGNOSIS

With CONSULT
Perform self-diagnosis for "ENGINE".
Is any error system detected?
YES- Check the DTC. Testing and Inspection (VQ-37VHR), Testing and Inspection (VK-56VD).
NO- GO TO 2.

2. CHECK ENGINE SPEED SIGNAL CIRCUIT

1.Turn the ignition switch OFF.
2.Disconnect ECM harness connectors.
3.Disconnect power steering control unit harness connector.
4.Check the continuity between ECM harness connector and power steering control unit harness connector.





*1: VQ-37VHR
*2: VK-56VD
Is the inspection result normal?
YES- GO TO 3.
NO- Repair or replace damaged parts.

3. CHECK ENGINE SPEED SIGNAL (ECM)

1.Connect ECM harness connectors.
2.Check the signal between ECM harness connector and ground with oscilloscope.





*1: VQ-37VHR
*2: VK-56VD
Is the inspection result normal?
YES- GO TO 4.
NO- Replace ECM. Description (VQ-37VHR), Description (VK-56VD).

4. CHECK ENGINE SPEED SIGNAL (POWER STEERING CONTROL UNIT)

1.Turn the ignition switch OFF.
2.Connect power steering control unit harness connector.
3.Check the signal between power steering control unit harness connector and ground with oscilloscope.





Is the inspection result normal?
YES- GO TO 5.
NO- Replace power steering control unit. Removal And Installation Without 4WAS.

5. CHECK TERMINALS AND HARNESS CONNECTORS

- Check the power steering control unit pin terminals for damage or loose connection with harness connector.
- Check ECM pin terminals for damage or loose connection with harness connector.
Is the inspection result normal?
YES- INSPECTION END
NO- Repair or replace damaged parts.