Lexus RX (RX 350L, RX450h) 2016-2024 Repair Manual: Operation Check

OPERATION CHECK

CHECK POWER SEAT FUNCTION

(a) Check the basic functions.

(1) Operate the power seat switches and check that the following seat functions operate properly:

CHECK POWER SEAT MOTOR (SLIDING, FRONT VERTICAL, LIFTER AND RECLINING FUNCTIONS)

(a) Check the PTC operation inside the power seat motor.

HINT:

The resistance of the PTC thermistor increases when a switch of the position control ECU and switch assembly LH is held down even after the seat has been moved to the farthest possible position in one direction. If the resistance increases beyond a specified level, the current is shut off to prevent a short circuit.

(1) Choose a power seat function. Operate a switch of the position control ECU and switch assembly LH and move the seat to the farthest possible position in one direction. Keep the seat in that position for approximately 60 seconds.

(2) Operate the switch of the position control ECU and switch assembly LH again and continue to try to move the seat in the same direction as in the previous step. Measure the time until the current is shut off (motor operation sound stops).

Standard:

4 to 90 seconds

(3) After the current is shut off, release the switch of the position control ECU and switch assembly LH and wait for approximately 60 seconds.

(4) Operate a switch of the position control ECU and switch assembly LH and move the seat in the opposite direction. Check that the motor operates.

CHECK SEAT LENGTH MOTOR (w/ Seat Variable Cushion Switch)

(a) Check the PTC operation inside the seat length motor.

NOTICE:

The inspection should be performed with the seat installed in the vehicle.

(1) Operate the seat variable cushion switch and move the seat cushion to either the foremost or rearmost position. Keep the seat in that position for approximately 60 seconds.

(2) Operate the seat variable cushion switch again and continue to try to move the seat cushion in the same direction as in the previous step. Measure the time until the current is shut off (motor operation sound will stop).

Standard:

4 to 90 seconds

(3) After the current is shut off, release the seat variable cushion switch and wait for approximately 60 seconds.

(4) Operate the seat variable cushion switch and move the seat cushion in the opposite direction. Check that the motor operates.

CHECK LUMBAR SUPPORT ADJUSTMENT MOTOR

(a) Check the PTC operation inside the lumbar support adjustment motor (forward - back).

NOTICE:

The inspection should be performed with the seat installed to the vehicle.

(1) Operate the front lumbar power seat switch and move the lumbar support to either the foremost or rearmost position. Keep the seat in that position for approximately 60 seconds.

(2) Operate the front lumbar power seat switch again and continue to try to move the lumbar support in the same direction as in the previous step. Measure the time until the current is shut off (motor operation sound stops).

Standard:

4 to 90 seconds

(3) After the current is shut off, release the front lumbar power seat switch and wait for approximately 60 seconds.

(4) Operate the front lumbar power seat switch and move the lumbar support in the opposite direction. Check that the motor operates.

(b) Check the PTC operation inside the lumbar support adjustment motor (up - down) (w/ Seat Variable Cushion Switch).

NOTICE:

The inspection should be performed with the seat installed to the vehicle.

(1) Operate the front lumbar power seat switch and move the lumbar support to either the foremost or rearmost position. Keep the seat in that position for approximately 60 seconds.

(2) Operate the front lumbar power seat switch again and continue to try to move the lumbar support in the same direction as in the previous step. Measure the time until the current is shut off (motor operation sound stops).

Standard:

4 to 90 seconds

(3) After the current is shut off, release the front lumbar power seat switch and wait for approximately 60 seconds.

(4) Operate the front lumbar power seat switch and move the lumbar support in the opposite direction. Check that the motor operates.

CHECK POWER SEAT POWER EASY ACCESS SYSTEM

HINT:

When troubleshooting a function, first make sure that the function is set to the default setting.

Click here

(a) Check that the seat slides backward when either of the following conditions is met:

(b) Check that the seat slides forward when either of the following conditions is met:

CHECK SEAT POSITION MEMORY AND RESTORING FUNCTION

(a) Turn the engine switch on (IG) and check that the P position indicator is illuminated.

(b) Move the seat to the foremost and uppermost positions using the position control ECU and switch assembly LH.

(c) Check that a buzzer sounds for 0.5 seconds and the seat position is memorized when the M1 switch is pressed within 3 seconds of the SET switch being pressed or the M1 switch is pressed while the SET switch is being pressed.

(d) Move the seat out of the foremost and uppermost positions using the position control ECU and switch assembly LH.

(e) Check that the buzzer sounds for 0.5 seconds and the seat position is memorized when the M2 switch is pressed within 3 seconds of the SET switch being pressed or the M2 switch is pressed while the SET switch is being pressed.

(f) Move the seat to the rearmost and lowermost positions using the position control ECU and switch assembly LH.

(g) Check that the buzzer sounds for 0.5 seconds and the seat position is memorized when the M3 switch is pressed within 3 seconds of the SET switch being pressed or the M3 switch is pressed while the SET switch is being pressed.

(h) Check that the buzzer sounds for 0.1 seconds and the seat automatically moves into the foremost and uppermost positions (memorized positions) when the M1 switch is pressed.

(i) Check that the buzzer sounds for 0.1 seconds and the seat automatically moves out of the foremost and uppermost positions (memorized positions) when the M2 switch is pressed.

(j) Check that the buzzer sounds for 0.1 seconds and the seat automatically moves into the rearmost and lowermost positions (memorized positions) when the M3 switch is pressed.

(k) Turn the engine switch off and open the driver door. Check that the buzzer sounds for 0.1 seconds and the seat automatically moves to the memorized position by pressing the M1, M2 or M3 switch within 180 seconds after the engine switch is turned off.

(l) Turn the engine switch off and close the driver door. Check that the buzzer sounds for 0.1 seconds and the seat automatically moves to the memorized position by pressing the M1, M2 or M3 switch within 60 seconds after the engine switch is turned off.

(m) Operate the front vertical function of the position control ECU and switch assembly LH to tilt the seat down 3 times.

Within 10 seconds after operating the front vertical function of the position control ECU and switch assembly LH, operate the lifter function of the position control ECU and switch assembly LH and the reclining function of the position control ECU and switch assembly LH to raise and recline the seat simultaneously. Hold both switches for 10 seconds to clear the memory.

HINT:

The buzzer sounds for 0.5 seconds when the memory is cleared.

CHECK MEMORY CALL FUNCTION

(a) Automatic memory call function

(1) Prepare 2 electrical key transmitter sub-assemblies and label them electrical key transmitter sub-assembly A and electrical key transmitter sub-assembly B.

NOTICE:

Prepare 2 electrical key transmitter sub-assemblies which have already been registered to the vehicle and can be used to lock and unlock the doors normally.

(2) Register a seat position to the seat memory switch LH (M1) and the electrical key transmitter sub-assembly A.

HINT:

Refer to Memory Call Registration.

Click here

(3) While carrying the electrical key transmitter sub-assembly A, unlock the driver door using the entry unlock function or wireless unlock operation. Open the driver door and check that a buzzer sounds for 0.1 seconds and the driver seat moves to the memorized position.

HINT:

When the customize function "Seat Move Distance" is set to "Standard", the seat slides backward to a position 50 mm (1.97 in) from the memorized position.

Click here

(4) Register a seat position to the seat memory switch LH (M2) and the electrical key transmitter sub-assembly B.

HINT:

Refer to Memory Call Registration.

(5) While carrying the electrical key transmitter sub-assembly B, unlock the driver door using the entry unlock function or wireless unlock operation. Open the driver door and check that a buzzer sounds for 0.1 seconds and the driver seat moves to the memorized position.

HINT:

When the customize function "Seat Move Distance" is set to "Standard", the seat slides backward to a position 50 mm (1.97 in) from the memorized position.

Click here

CHECK MEMORY CALL EMERGENCY STOP FUNCTION

(a) While a memory call function is operating, check that performing one of the following will stop the memory call operation: 1) press the SET switch, M1 switch, M2 switch or M3 switch or 2) press the position control ECU and switch assembly LH.