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.
2004 Toyota Tundra Base, AutomaticFACTORY OEM SERVICE PROCEDURE
Multiplex Control Systems DTCS
MULTIPLEX CONTROL SYSTEMS DIAGNOSTIC TROUBLE CODES (DTC) IDENTIFICATION
| DTC | Description |
|---|---|
| DTC B1211/11 | Driver door ECU communication stop |
| DTC B1212/12 | Passenger door ECU communication stop |
| DTC B1214/14, B1215/15 | Communication bus malfunction (+B short/GND short) |
| DTC B1221/21, B1222/22, B1223/23, B1224/24 | Power window switch circuit on door & Door lock switch circuit on door |
| DTC B1242/42 | Wireless door lock tuner circuit malfunction |
| DTC B1273/73 | Sliding roof ECU communication stop (w/ Sliding roof vehicle only) |
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.