Engine Coolant Temperature Receiver Gauge Malfunction

DESCRIPTION

1. In this circuit, the meter CPU receives engine coolant temperature signals from the ECM using the CAN lines.
   
2. The meter CPU displays engine coolant temperature that is calculated based on the data received from the ECM.
   

WIRING DIAGRAM

INSPECTION PROCEDURE

HINT:

If there is an open or short in the engine coolant temperature sensor circuit, the ECM will store the DTCs. Perform troubleshooting of the "SFI System" (Click here).

1. CHECK CAN COMMUNICATION SYSTEM

1. Check if CAN communication DTC is output (Click here(for LHD), Click here (for RHD)).
   

   Result:

   Condition	Proceed to
   DTC is not output	A
   DTC is output	B

B	REPAIR CIRCUITS INDICATED BY OUTPUT DTCS

A

2. CHECK MULTIPLEX COMMUNICATION SYSTEM

1. Check if MULTIPLEX communication DTC is output (Click here).
   

   Result:

   Condition	Proceed to
   DTC is not output	A
   DTC is output	B

B	REPAIR CIRCUITS INDICATED BY OUTPUT DTCS

B

3. PERFORM ACTIVE TEST BY INTELLIGENT TESTER

1. Connect the intelligent tester to the DLC3.

2. Engine switch on (IG).

3. Turn the tester ON.

4. Enter the following menus: Diagnosis / Body / Combination Meter / Active Test.

5. Check the values by referring to the values in the table below.

   Combination Meter: 

   Item	Test Details	Diagnostic Note
   COOLANT TEMP	LOW, NORMAL, HI	-

   OK:

   Needle indication is normal.
   

NG	REPLACE COMBINATION METER ASSEMBLY

OK

4. READ VALUE OF INTELLIGENT TESTER

1. Connect the intelligent tester to the DLC3.

2. Engine switch on (IG).

3. Turn the tester ON.

4. Enter the following menus: Diagnosis / Power Train / Engine / Data List.

5. Check the values by referring to the values in the table below.

   Engine: 

   Item	Measurement Item/Range (Display)	Normal Condition	Diagnostic Note
   Water Temperature Meter Operation	Engine coolant temp: -40°C (-40°F) to 140°C (284°F)	After warming up: 80 to 95°C (176 to 203°F)	-

OK:

Engine coolant temperature value displayed on the tester is almost the same as needle indication.

NG	GO TO SFI SYSTEM

OK

5. REPLACE COMBINATION METER ASSEMBLY

OK:

The operation of the combination meter assembly returns to normal.

NG	REPLACE ECM

OK
END