Seat Heater System: Inspection

WARNING: This page is about a different car, the 2002 Toyota Sequoia. However, it is still accessible from the selected car via links, so may be relevant.

Inspect seat switch continuity :

Fig 1: Identifying Seat Switches & Terminals
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Fig 2: Seat Switch Specifications
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

If continuity is not as specified, replace the switch.
Inspect seat heater indicator light operation :
1. Connect the positive (+) lead from the battery to terminal 4 and the negative (-) lead to terminal 6.
  
  Fig 3: Testing Seat Heater Indicator Light
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Push the seat heater switch Right or Left side and check that the indicator light lights up.
  If operation is not as specified, replace the switch and inspect the circuits connected to other parts.
Inspect seat heater cushion continuity :
1. Heat the thermostat with a light.
  
  Fig 4: Applying Heat Lamp To Seat Heater Cushion Thermostat & Identifying Terminals
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Inspect the seat heater cushion continuity between terminals.
  
  Fig 5: Seat Heater Cushion Thermostat Terminal Specifications
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
If continuity is not as specified, replace the seat cushion pad.
Inspect seat back continuity :
1. Heat the thermostat with a light.
  
  Fig 6: Testing Seat Back Thermostat & Identifying Terminals
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Inspect the seat heater cushion continuity between terminals.
  
  Fig 7: Seat Back Thermostat Terminal Specifications
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  If continuity is not as specified, replace the seat back pad.
Inspect seat heater cushion continuity :
Inspect the seat heater inner cushion and front cushion continuity between terminals, as shown.

Fig 8: Identifying Seat Heater Cushion Terminals (Wire Harness Side)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Fig 9: Seat Heater Cushion Terminal Specifications
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

If continuity is not as specified, replace the seat back pad.
Inspect seat back continuity :
Inspect the seat back continuity between terminals.

Fig 10: Identifying Seat Back Terminals (Wire Harness Side)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Fig 11: Seat Back Terminal Specifications
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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