Diagnosis Procedure

1. Turn ignition switch OFF.
2. Disconnect rear seatback heater connector.
3. Turn ignition switch ON.
4. Check voltage between rear seatback heater harness connector and ground.

   (+)			(-)	Condition		Voltage (V) (Approx.)
   Rear seatback heater
   Connector		Terminal
   LH	B646	3	Ground	Rear heated seat switch	HI mode	12
   					Other than the above	0
   		1			LO mode	12
   					Other than the above	0
   RH	B645	3			HI mode	12
   					Other than the above	0
   		1			LO mode	12
   					Other than the above	0

Is the inspection result normal?

YES

GO TO 4.

NO

GO TO 2.

1. Turn ignition switch OFF.
2. Disconnect rear seat cushion heater connector.
3. Check continuity between rear seatback heater harness connector and rear seat cushion heater harness connector.

   Rear seatback heater			Rear heated seat control unit		Continuity
   Connector		Terminal	Connector	Terminal
   LH	B646	3	B647	7	Existed
   RH	B645			5

4. Check continuity between rear seatback heater harness connector and ground.

   Rear seatback heater			Ground	Continuity
   Connector		Terminal
   LH	B646	3		Not existed
   RH	B645

Is the inspection result normal?

YES

GO TO 3.

NO

Repair or replace harness.

1. Check continuity between rear seatback heater harness connector and rear seat cushion heater harness connector.

   Rear seatback heater			Rear heated seat control unit		Continuity
   Connector		Terminal	Connector	Terminal
   LH	B646	1	B647	12	Existed
   RH	B645			2

2. Check continuity between rear seatback heater harness connector and ground.

   Rear seatback heater			Ground	Continuity
   Connector		Terminal
   LH	B646	1		Not existed
   RH	B645

Is the inspection result normal?

YES

Replace rear heated seat control unit.

NO

Repair or replace harness.

1. Turn ignition switch OFF.
2. Check continuity rear seatback heater harness connector and ground.

Is the inspection result normal?

YES

Replace rear seatback heater.

NO

Repair or replace harness.