Seat: Overview Lexus GX J120

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1. CHECK POWER SEAT FUNCTION Check the basic function. Check that each part functions properly (sliding, front vertical, lifter, reclining, lumbar support) when operating the power seat switches.
2. CHECK POWER SEAT MOTOR ASSY (SLIDING, FRONT VERTICAL, LIFTER, RECLINING FUNCTIONS) Inspect the PTC operation inside the power seat motor assy. NOTE: The inspection should be performed with the seat installed in the vehicle. Perform this inspection for every maximum position. Move the seat to any of the maximum positions by operating the power seat switch, and keep the seat there for approximately 60 seconds. Try to operate the power seat past the maximum position using the power seat switch and measure the time until the electrical current is shut off (motor operation sound will stop, inspection of current shut-off). Standard: Approx. 4 - 90 seconds Turn the power seat switch off after the inspection of current shut-off, and keep that condition for approximately 60 seconds. Operate the power seat switch to move the seat to the opposite position and check that the motor operates.
3. CHECK LUMBAR SUPPORT ADJUSTER ASSY LH Inspect the PTC operation inside the power seat motor. NOTE: The inspection should be performed with the seat installed to the vehicle. Move the lumbar support to either the foremost or rearmost position by operating the lumbar support switch, and keep it there for approximately 60 seconds. Try to move the lumbar support past the maximum position using the switch and measure the time until the electrical current is shut off (motor operation sound will stop, inspection of current shut-off). Standard: Approx. 4 - 90 seconds Turn the lumbar support switch off after the inspection of current shut-off, and keep that condition for approximately 60 seconds. Operate the lumbar support switch to move the lumbar support to the opposite position and check that the motor operates.
4. CHECK MEMORY AND REACTIVATION FUNCTION (w/ MEMORY) Turn the ignition switch ON and move the shift lever into the P range. Move the seat into the foremost position and uppermost position using each seat switch. Check that the buzzer sounds for 0.5 second and the seat position is recorded when the M1 switch is pressed while the SET switch is held down. Move the seat out of the foremost position and uppermost position using each seat switch. Check that the buzzer sounds for 0.5 second and the seat position is recorded when the M2 switch is pressed while the SET switch is held down. Check that the buzzer sounds for 0.1 second and the seat automatically moves into the foremost position and uppermost position (set positions) when the M1 switch is pressed. Check that the buzzer sounds for 0.1 second and the seat automatically moves out of the foremost position and uppermost position (set positions) when the M2 switch is pressed. Check that the seat automatically moves into the set position when the M1 or M2 switch is pressed within 30 seconds after the ignition switch is turned OFF, the key is pulled out from the key cylinder and the driver side door is opened. Move the seat into the maximum positions of the slide movement, and disconnect the negative terminal of the battery while the memory switch is pressed. Then leave the seat in the position for 3 minutes. The seat position memory will be erased. Move the seat into all the maximum positions (front/rear and up/down) using each seat switch. Check that the seat does not move (the seat position is not recorded) when the M1 switch or the M2 switch is pressed, after the M1 switch 1 and M2 switch are pressed at one time while the SET switch is held down.
5. INITIALIZATION CHECK (w/ MEMORY) When replacing the power seat switch (seat ECU), perform an initialization by moving the power seat into the foremost and uppermost position. When replacing the D/C OUT fuse, perform an initialization by moving the power seat into the foremost and uppermost position.

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1. INSPECT SEAT MEMORY SWITCH (w/ MEMORY) Inspect the switch continuity. Standard: SEAT MEMORY SWITCH (w/ MEMORY) Terminal No. Switch Position Specified Condition 1 <=> 2 SET Switch ON Continuity 2 <=> 3 SW1 Switch ON Continuity 2 <=> 4 SW2 Switch ON Continuity If the result is not as specified, replace the switch assy.
2. INSPECT FRONT POWER SEAT SWITCH LH (w/o MEMORY) Inspect the continuity between the terminals when each switch is operated. Standard (Slide switch): Standard (Front vertical switch): Standard (Lifter switch): Standard (Reclining switch): If the result is not as specified, replace the front power seat switch.
3. INSPECT FRONT POWER SEAT SWITCH RH Inspect the continuity between the terminals when each switch is operated. Standard (Slide switch): Standard (Reclining switch): If the result is not as specified, replace the front power seat switch.
4. INSPECT POWER SEAT SWITCH ASSY (LUMBAR SUPPORT) Inspect the continuity between the terminals when the switch is operated. Standard: If the result is not as specified, replace the power seat switch assy.
5. INSPECT FRONT SEAT ADJUSTER ASSY Inspect operation of the slide motor. Check that the motor rotates smoothly when the battery is connected to the slide motor connector terminals. Standards: If the result is not as specified, replace the slide motor. LH side: Inspect operation of the front vertical motor. Check that the motor rotates smoothly when the battery is connected to the front vertical motor connector terminals. Standard: If the result is not as specified, replace the front vertical motor. LH side: Inspect operation of the lifter motor. Check that the motor rotates smoothly when the battery is connected to the lifter motor connector terminals. Standard: If the result is not as specified, replace the lifter motor. Inspect operation of the reclining motor. Check that the motor rotates smoothly when the battery is connected to the reclining motor connector terminals. Standard: If the result is not as specified, replace the reclining motor.
6. LH side: INSPECT LUMBAR SUPPORT ADJUSTER ASSY Inspect operation of the motor. Standard: If the result is not as specified, replace the lumbar support adjuster motor.

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1. CHECK SEAT HEATER CONTROL Disconnect the connector from the seat heater control assy. Check the voltage or continuity of each terminal of the wire harness side connector. Standard: SEAT HEATER CONTROL Terminal No. Condition Specified Condition 6 <=> Body ground Constant Continuity 1 <=> 6 (Seat heater switch) OFF -> ON O V -> 10 - 14 V 4 <=> 6 Constant 10 - 14 V If the result is not as specified, there may be a malfunction on the wire harness side or seat heater switch.

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1. INSPECT SEAT HEATER SWITCH LH Inspect the continuity between the terminals when the switch is operated. Standard: SEAT HEATER SWITCH LH Terminal No. Switch Position Specified Condition 3 <=> 4 ON (Max.) Continuity 1 <=> 3 OFF No continuity 2 <=> 3 ON (Min.) Continuity 5 <=> 6 Illumination circuit Continuity Inspect the seat heater switch indicator light. Connect the positive (+) lead from the battery to terminal 3 and the negative (-) lead to terminal 1. Push the seat heater switch ON and check that the indicator light lights up. If the result is not as specified, replace the seat heater switch and inspect the circuits connected to the other parts. Inspect the seat heater switch illumination. Connect the positive (+) lead from the battery to terminal 6 and the negative (-) lead to terminal 5. Check that the switch illuminates. If the result is not as specified, replace the seat heater switch or bulb.
2. INSPECT SEAT HEATER SWITCH RH Inspect the continuity between the terminals when the switch is operated. Standard: SEAT HEATER SWITCH RH Terminal No. Switch Position Specified Condition 3 <=> 4 ON (Max.) Continuity 1 <=> 3 OFF No continuity 2 <=> 3 ON (Min.) Continuity 5 <=> 6 Illumination circuit Continuity Inspect the seat heater switch indicator light. Connect the positive (+) lead from the battery to terminal 3 and the negative (-) lead to terminal 1. Push the seat heater switch ON and check that the indicator light lights up. If the result is not as specified, replace the seat heater switch and inspect the circuits connected to the other parts. Inspect the seat heater switch illumination. Connect the positive (+) lead from the battery to terminal 6 and the negative (-) lead to terminal 5. Check that the switch illuminates. If the result is not as specified, replace the seat heater switch or bulb.
3. INSPECT FRONT SEAT BACK HEATER ASSY LH Inspect the seatback heater assembly RH continuity. Standard: FRONT SEAT BACK HEATER ASSY LH Terminal No. Condition Specified Condition 1 <=> 2 Constant Continuity If continuity is not as specified, replace the seatback cover assy.
4. INSPECT FRONT SEAT BACK HEATER ASSY RH Inspect the seatback heater assembly RH continuity. Standard: FRONT SEAT BACK HEATER ASSY RH Terminal No. Condition Specified Condition 1 <=> 2 Constant Continuity If continuity is not as specified, replace the seatback cover assy.
5. INSPECT FRONT SEAT CUSHION HEATER ASSY LH Inspect the seat cushion heater continuity. Inspect the seat cushion heater continuity between the terminals. Standard: If the result is not as specified, replace the seat cushion cover assy.
6. INSPECT FRONT SEAT CUSHION HEATER ASSY RH Inspect the seat cushion heater continuity. Inspect the seat cushion heater continuity between the terminals. Standard: If the result is not as specified, replace the seat cushion cover assy.

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