Multiplex communication

Diagnostic trouble code chart

44steps
~264min
4/5difficulty
Done 0 of 44

If a malfunction code is displayed during the DTC check, check the circuit listed for that code in the chart below (Proceed to the page given for that circuit).

MULTIPLEX COMMUNICATION SYSTEM

DTC Code

Detection Item

Trouble Area

B1200 MPX Body ECU Stop
  1. Multiplex network body ECU
  2. Wire harness
B1208 Passenger Side Outer Mirror ECU
  1. Outer mirror control ECU RH
  2. Wire harness
B1209 Driver Side Outer Mirror
  1. Outer mirror control ECU LH
  2. Wire harness
B1214 Short to B+ in Door System Communication Bus Malfunction
  1. Multiplex network gateway ECU
  2. Multiplex network body ECU
  3. Airbag sensor assembly
  4. A/C amplifier
  5. Combination meter
  6. Power slide door ECU LH
  7. Power slide door ECU RH
  8. Power back door ECU
  9. Seat position control ECU
  10. Outer mirror control ECU LH
  11. Outer mirror control ECU RH
  12. Wire harness
B1215 Short to GND in Door System Communication Bus Malfunction
  1. Multiplex network gateway ECU
  2. Multiplex network body ECU
  3. Airbag sensor assembly
  4. A/C amplifier
  5. Combination meter
  6. Power slide door ECU LH
  7. Power slide door ECU RH
  8. Power back door ECU
  9. Seat position control ECU
  10. Outer mirror control ECU LH
  11. Outer mirror control ECU RH
  12. Wire harness
B1216 Rear Door ECU RH Communication Stop
  1. Power slide door ECU RH
  2. Wire harness
B1217 Rear Door ECU LH Communication Stop
  1. Power slide door ECU LH
  2. Wire harness
B1262 A/C ECU Communication Stop
  1. A/C amplifier
  2. Wire harness
B1271 Combination Meter ECU Communication Stop
  1. Combination meter
  2. Wire harness
B1272 Power Seat ECU Communication Stop
  1. Seat position control ECU
  2. Wire harness
B1281 Airbag ECU Communication Stop
  1. Airbag sensor assembly
  2. Wire harness
B1287 Back Door ECU Communication Stop
  1. Power back door ECU
  2. Wire harness

HINT: When DTCs indicating "+B or GND short malfunction of communication bus" (B1214, B1215) are detected at the same time as DTCs indicating "communication stop" (B1200, B1208, etc.), repair DTCs indicating "+B or GND short malfunction of communication bus" first.

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