Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2003 Lexus IS 300 Base, AutomaticFACTORY OEM SERVICE PROCEDURE
Power Window Motor PTC Operation
- Disconnect the connector from the master switch.
- 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 .
- Continue to apply voltage, check that there is a PTC operation noise within approximately 4-90 seconds.
- Reverse the polarity and check that the window begins to descend within approximately 60 seconds.
- If operation is not as specified, replace the motor. See POWER WINDOW REGULATOR MOTOR (FRONT) or POWER WINDOW REGULATOR MOTOR (REAR) under REMOVAL & INSTALLATION.
Factory Service Tools
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.