Inspection Procedure

1. Check that the tachometer operates properly while the engine is idling.

   OK: 

   Tachometer operate properly while engine is idling. 

OK: REPLACE COMBINATION METER (METER ECU) 

NG: GO TO Next Step 

1. Disconnect the K31 meter connector.
2. Measure the resistance and voltage of the wire harness side connector.

   Standard Resistance 

   TESTER CONNECTION SPECIFIED CONDITION
   
   

   Tester Connection	Specified Condition
   K31-40 (E2) - Body ground	Below 1 Ω

   Standard Voltage 

   TESTER CONNECTION SPECIFIED CONDITION
   
   

   Tester Connection	Specified Condition
   K31-21 (B) - Body ground	10 to 14 V

   Fig 1: Identifying K31 Meter Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: GO TO Next Step 

Fig 2: Identifying K31 Meter, K44 Sensor And K66 ECU Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Disconnect the K31 meter connector.
2. Disconnect the K66 ECU connector.
3. Disconnect the K44 sensor connector.
4. Measure the resistance of the wire harness side connectors.

   Standard resistance 

   TESTER CONNECTION SPECIFIED CONDITION
   
   

   Tester Condition	Specified Condition
   K31-25 (MPX+) - K66 - 13 (MPI2)	Below 1 Ω
   K31-5 (MPX-) - K44 - 13 (MPX1)	Below 1 Ω

   Result 

   RESULT REFERENCE CHART
   
   

   Result	Proceed to
   Both are OK	A
   One is OK	B
   Both are NG	C

B: REPAIR OR REPLACE COMBINATION METER ASSEMBLY AND WIRE HARNESS OR CONNECTOR 

C: REPAIR OR REPLACE HARNESS OR CONNECTOR 

A: REPLACE COMBINATION METER (METER ECU)