Toyota Sienna Quiz
Multiplex communication

A/C ECU Communication 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
4steps
~24min
2/5difficulty
Done 0 of 4

DTC B1262 A/C ECU Communication Stop

DESCRIPTION

DTC B1262 is output when communication between the A/C amplifier and the multiplex network gateway ECU stops for more than 10 seconds.

DTC No.

DTC Detection Condition

Trouble Area

B1262

 A/C ECU communication stops
  • A/C amplifier
  • Wire harness

WIRING DIAGRAM

WIRING DIAGRAM

INSPECTION PROCEDURE

1 CHECK HARNESS AND CONNECTOR (A/C AMPLIFIER - BATTERY)

CHECK HARNESS AND CONNECTOR
  1. Disconnect the A9 connector.
  2. Measure the voltage according to the value(s) in the table below.

Standard voltage

Standard voltage

HINT:
*1: for Automatic A/C
*2: for Manual A/C

2 CHECK HARNESS AND CONNECTOR (A/C AMPLIFIER - GROUND)

CHECK HARNESS AND CONNECTOR
  1. Measure the resistance according to the value(s) in the table below.

Standard resistance

Standard resistance

HINT:
*1: for Automatic A/C
*2: for Manual A/C

3 CHECK COMMUNICATION LINE

CHECK COMMUNICATION LINE
  1. Disconnect the C10 and A21 connectors.
  2. Measure the resistance according to the value(s) in the table below.

Standard resistance

Standard resistance

HINT:
*1: for Automatic A/C
*2: for Manual A/C

Result

Result

REPLACE A/C AMPLIFIER

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