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 99 (Multiplex Control Systems)
WARNING: This page is about a different car, the 2002 Toyota Avalon. 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
- Diagnostic Tests
- DTC B1211/11: Driver Door Ecu Communication Stopped
- DTC B1212/12: Front Passenger Door Ecu Communication Stopped
- DTC B1214/14: System Communication Bus Malfunction (Short To Voltage) Or DTC B1215/15: System Communication Bus Malfunction (Short To Ground)
- DTC B1221/21: Driver Door Power Window Switch Circuit Malfunction
- DTC B1222/22: Driver Door Power Door Lock Switch Circuit Malfunction
- DTC B1223/23: Front Passenger Door Power Window Switch Circuit Malfunction
- DTC B1224/24: Passenger Door Lock Switch Circuit Malfunction
- DTC B1231/31: Driver Door Jam Protection Limit Switch Circuit Malfunction
- DTC B1232/32: Driver Door Jam Protection Pulse Switch Circuit Malfunction
- DTC B1241/41: Body Control Ecu Switch Circuit Diagnosis
- DTC B1242/42: Wireless Door Lock Control Receiver Malfunction
- DTC B1243/43: GSW Terminal Circuit To Center Air Bag Sensor Assembly Malfunction
- DTC B1244/44: Automatic Light Control Sensor Circuit Malfunction
- DTC B1251/51: Power Mirror Switch Circuit Malfunction
- DTC B1269/69: Theft Deterrent Ecu Communication Stopped
- DTC B1272/72: Power Seat Ecu Communication Stopped
- Removal & Installation
- Wiring Diagrams
Factory Service Tools
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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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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