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.
1998 Lexus LS 400FACTORY OEM SERVICE PROCEDURE
Body Control System
- Description & Operation
- Trouble Shooting
- Circuit Tests
- Power Window Master Switch Circuit
- Passenger Door Lock Control Switch Circuit
- Driver Door Key Lock & Unlock Switch Circuit
- Passenger Door Key Lock & Unlock Switch Circuit
- Key Unlock Warning Switch Circuit
- Luggage Compartment Door Opener Switch Circuit
- Luggage Compartment Door Opener Motor Circuit
- Wireless Door Lock Tuner Circuit
- Driver Door Unlock Detection Switch Circuit
- Passenger Door Unlock Detection Switch Circuit
- Left Rear Door Unlock Detection Switch Circuit
- Right Rear Door Unlock Detection Switch Circuit
- Driver Door Courtesy Light & Courtesy Switch Circuit
- Passenger Door Courtesy Light & Courtesy Switch Circuit
- Left Rear Door Courtesy Light & Courtesy Switch Circuit
- Right Rear Door Courtesy Light & Courtesy Switch Circuit
- Wireless Door Lock Buzzer Circuit
- Anti-Theft Indicator Circuit
- Engine Hood Courtesy Switch Circuit
- Luggage Compartment Door Courtesy Switch Circuit
- Headlight Relay Circuit
- Taillight Relay Circuit
- Hazard Switch Circuit
- Anti-Theft Horn Circuit
- Standard Horn Circuit
- Wiper/Washer Switch Circuit
- Wiper Motor Circuit
- Light Sensor Circuit
- Headlight Control Switch Circuit
- Illumination Circuit
- Rheostat Light Control Circuit
- Component Tests
- Pin Voltage Tests
- Notes
- Body Control Ecu
- Notes
- B5-2 & B8-15
- B5-3 & B8-15
- B5-6 & B8-15
- B5-7 & B8-15
- B5-8 & B8-15
- B5-9 & B8-15
- B5-10 & B8-15
- B5-16 & B8-15
- B5-17 & B8-15
- B5-18 & B8-15
- B5-20 & Ground
- B6-7 & B8-15
- B6-8 & B8-15
- B6-9 & B8-15
- B6-10 & B8-15
- B6-17 & B8-15
- B6-21 & B8-15
- B7-1 & B8-15
- B7-3 & B8-15
- B7-4 & B8-15
- B7-8 & B8-15
- B7-10 & B8-15
- B8-1 & B8-15
- B8-2 & B8-15
- B8-5 & B8-15
- B8-6 & B8-15
- B8-7 & B8-15
- B8-8 & B8-15
- B8-9 & B8-15
- B8-11 & B8-15
- B8-15 & Ground
- 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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