Seat Temperature Element: Testing and Inspection

SEAT HEATER SYSTEM

INSPECTION

1. WIRING DIAGRAM

2. SEAT HEATER UNIT
Disconnect the seat heater unit connector, and check the continuity between terminals of connector.

Connector & terminal

LHD side seat
Without power seat (R188)
No. 1 - No. 4:
No. 1 - No. 5:
No. 4 - No. 5:
With power seat (R189)
No. 2 - No. 6:
No. 2 - No. 7:
No. 6 - No. 7:

RHD side seat (R41)
No. 1 - No. 3:
No. 1 - No. 4:
No. 3 - No. 4:

If no continuity exists, replace the seat heater unit with a new part.

3. SEAT HEATER SWITCH

- CHECK THERMISTOR OUTPUT VOLTAGE
1. Connect the battery to the connector.

Connector terminals No. 2 (+):

2. Measure the voltage between connector and chassis ground.

Connector & terminal:
LHD side seat
(R43) No. 4 (+) - Chassis ground (-):

RHD side seat
(R42) No. 4 (+) - Chassis ground (-):

If voltage is not 1.5 V or more, replace the seat heater switch.

- CHECK SWITCH OUTPUT VOLTAGE
1. Connect the battery to the connector.

Connector terminals No. 2 (+):

2. Measure the voltage between connector and chassis ground while turning the switch to ON.

Connector & terminal:
LHD side seat
(R43) No. 3 (+) - Chassis ground (-):

RHD side seat
(R42) No. 3 (+) - Chassis ground (-):

If voltage does not change from 10 V or more to zero, replace the seat heater switch.