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Power Seat Control System: Inspection

INSPECT LUMBAR SUPPORT SWITCH CONTINUITY

Fig 1: Inspecting Lumbar Support Switch

G02846330

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

LUMBAR SUPPORT SWITCH CONTINUITY

Switch position	Tester connection	Specified condition
FORWARD	1 - 4, 2 - 3	Continuity
OFF	1 - 2 - 4	Continuity
RELEASE	1 - 2, 3 - 4	Continuity

If continuity is not as specified, replace the switch.

INSPECT LUMBAR SUPPORT SWITCH CIRCUIT

Disconnect the switch connector and connect the seat wire harness to the floor wire harness.
Inspect the connector on the wire harness side.

Fig 2: Inspecting Connector On Wire Harness Side

G02846331

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

SPECIFIED CONDITION

Tester connection	Condition	Specified condition
1 - Ground	Constant	Battery positive voltage
2 - Ground	Constant	Continuity

If circuit is not as specified, inspect the circuits connected to other parts.

INSPECT LUMBAR SUPPORT MOTOR OPERATION
1. Connect the positive (+) lead from the battery to terminal 1 and the negative (-) lead to terminal 2, check that the lumbar support moves to release side.
  
  Fig 3: Checking Lumbar Support Movement (To Release Side)
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Reverse the polarity, check that the lumbar support moves forward.
  
  Fig 4: Checking Lumbar Support Movement (Forward)
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
If operation is not as specified, replace the lumber support adjuster.
INSPECT LUMBAR SUPPORT MOTOR CIRCUIT BREAKER OPERATION
1. Connect the positive (+) lead from the battery to terminal 2 and the negative (-) lead to terminal 1 on the lumbar support motor connector and move the lumbar support to front end position.
  
  Fig 5: Checking Lumbar Support Motor Operation
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Continue to apply voltage, check that a circuit breaker operation noise can be heard within 4 to 60 seconds.
3. Reverse the polarity, check that the lumbar support begins to move release side with in approximately 60 seconds.
  
  Fig 6: Checking Lumbar Support Movement (To Release Side)
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
If operation is not as specified, replace the lumber support adjuster.