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.
2000 Lexus LS 400FACTORY OEM SERVICE PROCEDURE
Multiplex Control Systems
- Description & Operation
- Self-Diagnostics
- Diagnostic Tests
- Notes
- DTC B1211/11: Driver's Door Ecu To Body Ecu Communication
- DTC B1212/12: Passenger's Front Door Ecu To Body Ecu Communication
- DTC B1213/13: Tilt/Telescopic Ecu To Body Ecu Communication
- DTC B1214/14 & DTC B1215/15: Door System Bus Communication Circuit Short
- DTC B1216/16: Right Rear Door Ecu To Body Ecu Communication
- DTC B1217/17: Left Rear Door Ecu To Body Ecu Communication
- DTC B1221/21: Power Window Master Switch Circuit
- DTC B1222/22: Driver's Door Lock Control Switch Circuit
- DTC B1223/23: Passenger's Front Window Switch Circuit
- DTC B1224/24: Passenger's Door Lock Control Switch Circuit
- DTC B1225/25: Right Rear Window Switch Circuit
- DTC B1226/26: Left Rear Window Switch Circuit
- DTC B1231/31: Driver's Jam Protection Limit Switch Circuit
- DTC B1232/32: Driver's Jam Protection Pulse Switch Circuit
- DTC B1233/33: Passenger's Front Jam Protection Limit Switch Circuit
- DTC B1234/34: Passenger's Front Jam Protection Pulse Switch Circuit
- DTC B1235/35: Right Rear Jam Protection Limit Switch Circuit
- DTC B1236/36: Right Rear Jam Protection Pulse Switch Circuit
- DTC B1237/37: Left Rear Jam Protection Limit Switch Circuit
- DTC B1238/38: Left Rear Jam Protection Pulse Switch Circuit
- DTC B1241/41: Body Ecu Switch Circuit Diagnosis
- DTC B1242/42: Wireless Door Lock Tuner Circuit
- DTC B1243/43: GSW Circuit Malfunction
- DTC B1244/44: Light Sensor Circuit Malfunction
- DTC B1261/61: ECM To Body Ecu Communication
- DTC B1262/62: A/C Control Assembly To Body Ecu Communication
- DTC B1266/66 & DTC B1267/67: Instrument Panel Bus Communication Circuit Short
- DTC B1271/71: Combination Meter Ecu To Body Ecu Communication
- DTC B1272/72: Power Seat Ecu (W/Memory Seat) To Body Ecu Communication
- DTC B1273/73: Sliding Roof Control Relay To Body Ecu Communication
- DTC B1275/75: Accessory Bus To Body Ecu Communication
- 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.