Seat Heater System: Inspection

If continuity is not as specified, replace the switch.

Fig 1: Identifying Connector Terminal

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1. Connect the positive (+) lead from the battery to terminal 3 and the negative (-) lead to terminal 2.
2. Push the seat heater switch ON that the indicator light lights up.

   If operation is not as specified, replace the switch and inspect the circuits connected to other parts.

   Fig 2: Inspecting Seat Heater Indicator Light

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1. Heat the thermostat with a light.
2. Inspect the seat heater cushion continuity between terminals, as shown.
   Fig 3: Inspecting Seat Heater Cushion Continuity Between Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   SPECIFIED CONDITION CHART
   
   

   Tester connection	Condition	Specified condition
   A1 - B2	Seat heater temperature below 25 °C (77 °F)	Continuity
   A1 - B2	Seat heater temperature above 45 °C (113 °F)	No continuity
   A2 - B1	Always	Continuity
   A2 - C1	Always	Continuity
   B2 - C2	Always	Continuity

   If continuity is not as specified, replace the seat cushion pad.

Disconnect the connector from the seat heater cushion and inspect the connector on wire harness side, as shown.

Fig 4: Identifying Connector Terminal

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

If circuit is not as specified, inspect the wire harness.

Inspect the seat cushion front side continuity between terminals, as shown.

Fig 5: Identifying Connector Terminal

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

If continuity is not as specified, replace the seat cushion pad.

Inspect the seat back continuity between terminals, as shown.

Fig 6: Identifying Connector Terminal

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

If continuity is not as specified, replace the seat back pad.