Power Windows: Diagnosis Lexus LS II

TROUBLE SHOOTING

Note. Before proceeding with trouble shooting, check multiplex system for faults. See MULTIPLEX CONTROL SYSTEM article. If no faults are found in multiplex system, proceed with TROUBLE SHOOTING .

Ensure all component terminals and ground connections are clean and tight. Check possible faults in order listed. Repair or replace components and circuits as necessary.

DOOR OPEN DETECTION SWITCH TEST

For testing procedures, see ANTI-THEFT SYSTEM article.

WINDOW MOTOR TEST

1. Disconnect window motor connector. Apply battery voltage and ground between motor connector terminals. Motor should operate. To reverse motor direction, reverse polarity of voltage to motor. Replace motor if it does not operate.
2. If battery voltage continues to be applied to motor after window has stopped moving, a circuit breaker in motor should open in 4-90 seconds and motor should stop. After circuit breaker opens, reverse polarity of voltage to motor.
3. Within 60 seconds, motor should move in opposite direction, indicating circuit breaker has closed. Replace motor as necessary.

POWER MAIN RELAY TEST

Remove relay. Replace relay if it does not test as follows. (Scheme 1)

1. No continuity should exist between terminals No. 3 and 5.
2. Apply battery voltage and ground between terminals No. 1 and 2. Continuity should exist between terminals No. 3 and 5.

Scheme 1

MASTER SWITCH TEST

Remove master switch. Check for continuity between specified terminals of master switch. (Scheme 2) See MASTER SWITCH CONTINUITY TEST table. If continuity is not as specified, replace master switch.

MASTER SWITCH CONTINUITY TEST

Scheme 2