INSPECTION PROCEDURE 10: Engine Coolant Temperature Gauge does not Work (other meters work).

COMMENTS ON TROUBLE SYMPTOM

If only the engine coolant temperature gauge does not operate, the engine-ECU <M/T> or engine-A/T-ECU <A/T> system, the combination meter, the wiring harness or its connector may be defective.

POSSIBLE CAUSES

Damaged harness wires and connectors
Malfunction of engine-ECU <M/T> or engine-A/T-ECU <A/T>
Malfunction of combination meter

DIAGNOSTIC PROCEDURE

Step 1. M.U.T.-III CAN bus diagnostics

Use the M.U.T.-III to diagnose the CAN bus lines.

Q. Is the check result satisfactory?

	Go to Step 2.

	Repair the CAN bus lines (Refer to GROUP 54F, Diagnosis - Can Bus Diagnostic Table ). After diagnosing the CAN bus lines, go to Step 5.

Step 2. M.U.T.-III other system diagnosis code

Check if an MPI system diagnosis code is set.

Q. Is the diagnosis code set?

	Diagnose MPI system. (Refer to GROUP 13A, Troubleshooting or GROUP 13B, Troubleshooting .) After diagnosing the MPI system, go to Step 5.

	Go to Step 3.

Step 3. M.U.T.-III data list

Item No.8C: Water thermometer (Refer to .)
Item No.8E: Water thermometer definite flag (Refer to .)

Q. Is the check result satisfactory?

	Go to Step 4.

	Diagnose MPI system. (Refer to GROUP 13A, Troubleshooting or GROUP 13B, Troubleshooting .) After diagnosing the MPI system, go to Step 5.

Step 4. M.U.T.-III actuator test

Item No.88: Water temperature gauge: 0 °C
Item No.89: Water temperature gauge: 85 °C
Item No.8A: Water temperature gauge: 126 °C

OK: The water thermometer operates.

Q. Is the check result satisfactory?

	Go to Step 5.

	Replace combination meter and then go to step 5.

Step 5. Retest the system.

Check to see that the engine coolant temperature gauge operates normally.

Q. Is the check result satisfactory?

	The procedure is complete.

	Go to Step 1.