Power Windows: Overview Lexus IS I

DESCRIPTION & OPERATION

AUTO OPERATION (DRIVER'S WINDOW)

When the power window master switch is operated to AUTO UP position with the ignition on, the current flows from the D FR P/W fuse to the power window master switch TERMINAL 1 to TERMINAL 8 to the front LH power window motor TERMINAL 1 to TERMINAL 2 to the power window master switch TERMINAL 20 to TERMINAL 9 to GROUND, and the motor rotates to close the window. The motor continues to rotate until the window is fully closed or the DOWN position of the power window master switch is operated.

When the power window master switch is operated to AUTO DOWN position with the ignition on, the current flows from the D FR P/W fuse to the power window master switch TERMINAL 1 to TERMINAL 20 to the front LH power window motor TERMINAL 2 to TERMINAL 1 to the power window master switch TERMINAL 8 to TERMINAL 9 to GROUND, and the motor rotates to open the window. The motor continues to rotate until the window is fully opened or the UP position of the power window master switch is operated.

KEY OFF POWER WINDOW OPERATION

After the ignition turned off, the driver's side power window can be operated for approximately 45 seconds, unless the driver's side door is opened. However, if the key off operation time finishes during AUTO operation, the AUTO operation is stopped immediately.

MANUAL OPERATION (DRIVER'S WINDOW)

When the power window master switch is operated to UP position with the ignition on, the current flows from the D FR P/W fuse to the power window master switch TERMINAL 1 to TERMINAL 8 to the front LH power window motor TERMINAL 1 to TERMINAL 2 to the power window master switch TERMINAL 20 to TERMINAL 9 to GROUND, and the motor rotates to close the window.

When the power window master switch is operated DOWN position with the ignition on, the current flows from the D FR P/W fuse to the power window master switch TERMINAL 1 to TERMINAL 20 to the front LH power window motor TERMINAL 2 to TERMINAL 1 to the power window master switch TERMINAL 8 to TERMINAL 9 to GROUND, and the motor rotates to open the window.

MANUAL OPERATION (EXCEPT DRIVER'S WINDOW)

When the front RH, rear LH and rear RH power window control switch is operated to the UP position, the current flows to the power window control switch TERMINAL PCT (4) to TERMINAL U (5) of the power window motor to power window control switch TERMINAL D (2) to TERMINAL E (3) to GROUND, and the motor rotates to close the window.

When the front RH, rear LH and rear RH power window control switch is operated to DOWN position, the current flows to the power window control switch TERMINAL PCT (4) to TERMINAL D (2) to the power window motor to the power window control switch TERMINAL U (5) to TERMINAL E (3) to GROUND, and the motor rotates to open the window.

When controlling the respective windows with the power window master switch, a communication signal is input from the power window master switch TERMINAL TX (18) to body ECU TERMINAL MPX3 (6), and the current flows from the body ECU to the respective power window control switch TERMINAL SU (6), UP operation, and SD (1), DOWN operation, and the motor rotates in the controlled direction.

SYSTEM OPERATION CHECK

1. Trouble shooting of a power window system complaint begins with verification of the customer problem. If problem occurs, go to step 3 . If problem does not occur, go to next step.
2. If problem does not occur, review conditions under which problem occurred for customer and try to duplicate those conditions. For example, if the problem occurs on rainy days or during high humidity conditions, sprinkle water onto vehicle and see if malfunction occurs. DO NOT sprinkle water directly into engine compartment or onto electronic components. Visually inspect for signs of mechanical and electrical damage. Inspect for blown fuses and damaged relays. Inspect for loose or corroded connections, damaged wiring harnesses and/or switches. Check for a broken or partially broken wire inside insulation, which could cause system malfunction but prove good in a continuity/voltage check with system disconnected. Ensure any aftermarket electronic equipment is properly installed. If fault is found, repair as necessary.
3. Inspect the multiplex communication system and confirm that there is no trouble by the basic inspection and DTC check. See PRE-CHECK under SELF-DIAGNOSTIC under «MULTIPLEX COMMUNICATION SYSTEM»(ref-154087) article under COMMUNICATION DEVICES in ACCESSORIES & EQUIPMENT.
4. After repairs have been completed, confirm that problem has been eliminated. Operate the system under same conditions recorded for original complaint. If problem is no longer present, repair has corrected problem. If problem is still present, further diagnosis and repair is required.

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POWER WINDOW MOTOR PTC OPERATION

1. Disconnect the connector from the master switch.
2. Connect the positive (+) lead from the battery to terminal 1 and the negative (-) lead to terminal 2 on the wiring harness side connector and raise the window to fully closed position. See «CONNECTOR IDENTIFICATION»(ref-154768-S11332494392003052300000) .
3. Continue to apply voltage, check that there is a PTC operation noise within approximately 4-90 seconds.
4. Reverse the polarity and check that the window begins to descend within approximately 60 seconds.
5. If operation is not as specified, replace the motor. See «POWER WINDOW REGULATOR MOTOR (FRONT)»(ref-154768-S18404700652003052700000) or «POWER WINDOW REGULATOR MOTOR (REAR)»(ref-154768-S19756134432003052700000) under REMOVAL & INSTALLATION.