Engine Coolant Temperature Receiver Gauge Malfunction: Wiring Diagram

Fig 1: Engine Coolant Temperature Receiver Gauge - Wiring Diagram

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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" (See DATA LIST / ACTIVE TEST (for 2GR-FSE), See DATA LIST / ACTIVE TEST (for 4GRFSE)).

1. CHECK CAN COMMUNICATION SYSTEM 
   1. Check if CAN communication DTC is output (See SYSTEM DESCRIPTION ).

   Result 

   RESULT REFERENCE
   
   

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

   B : REPAIR CIRCUITS INDICATED BY OUTPUT DTCS 

   A : Go To Next Step 

2. CHECK MULTIPLEX COMMUNICATION SYSTEM 
   1. Check if MULTIPLEX communication DTC is output (See DTC CHECK/CLEAR ).

   Result 

   RESULT REFERENCE
   
   

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

   B : REPAIR CIRCUITS INDICATED BY OUTPUT DTCS 

   B : Go To Next Step 

3. PERFORM ACTIVE TEST BY INTELLIGENT TEST 
   1. Connect the intelligent tester to the DLC3.
   2. Engine switch on (IG).
   3. Turn the tester ON.
   4. Enter the following menus: DIAGNOSIS / OBD/MOBD / METER / ACTIVE TEST.
   5. Check the values by referring to the values in the table below.

   METER: 

   METER DIAGNOSTIC REFERENCE
   
   

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

   OK: 

   Needle indication is normal. 

   NG : REPLACE COMBINATION METER ASSEMBLY 

   OK : Go To Next Step 

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 / OBD/MOBD / ENGINE / DATA LIST.
   5. Check the values by referring to the values in the table below.

   ENGINE: 

   ENGINE DISPLAY DIAGNOSTIC REFERENCE
   
   

   Item	Measurement Item/Range (Display)	Normal Condition	Diagnostic Note
   WATER TEMP	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 : Go To Next Step 

5. REPLACE COMBINATION METER ASSEMBLY 

   OK: 

   The operation of the combination meter assembly returns to normal. 

   NG : REPLACE ECM 

   OK : END