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 LS 430FACTORY OEM SERVICE PROCEDURE
Section 148 (Body Control Systems)
WARNING: This page is about a different car, the 2003 Lexus GS 430, 2003 Lexus GS 300, 2002 Lexus GS 430, and 2002 Lexus GS 300. However, it is still accessible from the selected car via links, so may be relevant.
- Description & Operation
- Component Locations
- Trouble Shooting
- Self-Diagnostic System
- Connector Identification
- Circuit Tests
- Anti-Theft Horn Circuit
- Anti-Theft Indicator Circuit
- Brake Fluid Level Warning Switch Circuit
- Clock Circuit
- Driver Buckle Switch Circuit
- Generator "L" Terminal Circuit (W/ Daytime Running Lights Only)
- Hazard Switch Circuit
- Headlight Relay Circuit
- Heater Main Relay Circuit
- Hood Courtesy Switch Circuit
- Horn Circuit
- Illumination Circuit
- Key Unlock Warning Switch Circuit
- Lamp Failure Sensor Circuit
- Light Control Switch Circuit
- Luggage Compartment Door Lock & Unlock Switch Circuit
- Luggage Compartment Courtesy Switch Circuit
- Luggage Compartment Door Opener Motor Circuit
- Luggage Compartment Door Opener Switch Circuit
- Mirror Switch Circuit
- Parking Brake Switch Circuit
- Pattern Select Switch Circuit
- Power Source Circuit (Body Ecu No. 1)
- Power Source Circuit (Body Ecu No. 2)
- PWS Circuit
- Rear Defogger Relay Circuit
- Stop Light Switch Circuit
- Taillight Relay Circuit
- Wireless Door Lock Buzzer Circuit
- Wireless Door Lock Tuner Circuit
- Component Tests
- Pin Voltage Tests
- Removal & Installation
- Wiring Diagrams
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.
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