Many malfunctions in the electrical system are caused by poor harness and terminals.

Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.

Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.

Has a problem been found?

YES

Repair as necessary and go to "Verification of Vehicle Repair" procedure.

NO

Go to "Signal Circuit Inspection" procedure.

Ignition "OFF".

Disconnect ECT sensor connector.

Ignition "ON" & Engine "OFF".

Measure voltage between terminal 1 of the sensor harness connector and chassis ground.

Specification : Approx. 5V

Is the measured voltage within specifications?

YES

▶ Go to "Ground Circuit Inspection" procedure.

NO

▶ Check for open or short in the signal harness.

Repair as necessary and go to "Verification of Vehicle Repair" procedure.

Ignition "OFF".

Disconnect ECT sensor connector and ECM connector.

Measure resistance between terminal 3 of the sensor harness connector and terminal 4 of ECM harness connector.

Specification : Approx. below 1Ω

Is the measured resistance within specifications?

YES

▶ Go to "Component Inspection" procedure.

NO

Check for open in ground harness.

Repair as necessary and go to "Verification of Vehicle Repair" procedure .