2001 Toyota PriusFACTORY OEM SERVICE PROCEDURE

Multiplex Control System DTCS

MULTIPLEX CONTROL SYSTEM DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION

DTC Description
B1211 Driver's Door ECU Communication Stopped
B1221 Power Window Switch Circuit On Driver's Door
B1222 Door Lock Switch Circuit On Driver's Door
B1241 Body ECU Switch Circuit Diagnosis
B1242 Wireless Door Control Receiver Circuit Malfunction
B1248 AVC-LAN Circuit Communication Stopped
B1261 ECM Communication Stopped
B1262 A/C Amplifier Communication Stopped
B1266 Instrument Panel System Communication Bus Malfunction (B+ Shorted)
B1267 Instrument Panel System Communication Bus Malfunction (GND Shorted)
B1271 Combination Meter ECU Communication Stopped
B1274 Multi-Display Communication Stopped
B1293 Gateway ECU Communication Stopped
Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.