DTC    B1262    A/C ECU Communication Stop

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DESCRIPTION

  1. This DTC is detected when communication between the air conditioning amplifier (A/C ECU) and multiplex network gateway ECU stops for more than 10 seconds.

DTC No.
DTC Detection Condition
Trouble Area
B1262
Air conditioning amplifier (A/C ECU) communication stops
  1. Air conditioning amplifier (A/C ECU)
  2. Wire harness

WIRING DIAGRAM


B110977E02


INSPECTION PROCEDURE

HINT:
When "+B of GND short malfunction of communication bus" DTCs (B1266 and B1267) are detected at the same time as "communication stop" DTC B1262, repair the "+B or GND short malfunction of communication bus" DTCs first.

1.CHECK FUSE (ECU-IG No.1)

  1. Remove the ECU-IG No.1 fuse from the fusible link block.

  1. Measure the resistance of the fuse.

    Standard resistance:
    Below 1 Ω



NG
REPLACE FUSE
OK


2.CHECK WIRE HARNESS (AIR CONDITIONING AMPLIFIER ASSEMBLY - BATTERY AND BODY GROUND)


    E109218E28

  1. Disconnect the A11 ECU connector.

  1. Measure the voltage of the wire harness side connector.

    Standard voltage:
    Tester Connection
    		Condition
    		Specified Condition
    A11-1 (IG+) - Body ground
    		Ignition switch ON
    		10 to 14 V

  1. Measure the resistance of the wire harness side connector.

    Standard resistance:
    Tester Connection
    		Condition
    		Specified Condition
    A11-6 (GND) - Body ground
    		Always
    		Below 1 Ω



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


3.CHECK RESISTANCE OF COMMUNICATION LINE


  1. Disconnect the G1 and A24 ECU connectors.


    B111054E02

  1. Measure the resistance of the wire harness side connectors.


Standard resistance:

Tester Connection
Specified Condition
A11-4 (MPX-) - G1-4 (MPI1)
Below 1 Ω
A11-3 (MPX+) - A24-22 (MPX2)
Below 1 Ω



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY