Toyota Sienna Quiz
Multiplex communication

MPX Body ECU Stop

In this manual: Multiplex communication
Introduction — 55Service specifications — 7Maintenance — 7Engine — 264U151e automatic transaxle — 108Transfer — 19Propeller shaft — 8Drive shaft — 14Differential — 16Axle — 18Suspension — 37Tire and wheel — 54Brake control — 141Parking brake — 16Steering Column — 11Power steering — 18Air conditioning — 106Supplemental restraint system — 146Seat belt — 22Theft deterrent — 14Engine immobiliser — 17Cruise control — 65Lighting — 61Wiper and washer — 13Door lock — 42Meter — 28Audio / visual — 94Navigation — 108Park assist / monitoring — 33Horn — 5Garage door opener — 42GR-FE Engine control system — 126Supplemental restraint system — 147Other system — 14Windshield / windowglass — 43Mirror — 23Instrument panel — 6Seat belt — 22Seat — 92Engine hood / door — 104Exterior — 39Interior — 5Sliding roof — 9Multiplex communication — 18Can communication — 23
6steps
~36min
2/5difficulty
Done 0 of 6

DTC B1200 MPX Body ECU Stop

DESCRIPTION

This DTC is detected when communication between the multiplex network body ECU and the multiplex network gateway ECU stops for more than 10 seconds.

DTC No.

DTC Detection Condition

Trouble Area

B1200

 Body ECU communication stops
  • Multiplex network body ECU
  • Wire harness

WIRING DIAGRAM

WIRING DIAGRAM

INSPECTION PROCEDURE

1 CHECK HARNESS AND CONNECTOR (MULTIPLEX NETWORK BODY ECU - BATTERY)

CHECK HARNESS AND CONNECTOR
  1. Disconnect the 1A and 1C junction block connectors.
  2. Measure the voltage according to the value(s) in the table below.

Standard voltage

Standard voltage

2 CHECK HARNESS AND CONNECTOR (MULTIPLEX NETWORK BODY ECU - GROUND)

CHECK HARNESS AND CONNECTOR
  1. Disconnect the 1K and 1L junction connectors.
  2. Measure the resistance according to the value(s) in the table below.

Standard resistance

Standard resistance

3 CHECK COMMUNICATION LINE

CHECK COMMUNICATION LINE
  1. Disconnect the A21, G4 and B7 ECU connectors.
  2. Measure the resistance according to the value(s) in the table below.

Standard resistance

Standard resistance

Result

Result

REPLACE MULTIPLEX NETWORK BODY ECU

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