DTC    B1262    A/C ECU Communication Stop

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DESCRIPTION

  1. This DTC is detected when communication between the No. 2 A/C control amplifier (A/C ECU) and gateway ECU stops for more than 10 seconds.

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

WIRING DIAGRAM


B108877E06


INSPECTION PROCEDURE

1.CHECK OPERATION

  1. Check that the A/C switch can operate the A/C normally.

    OK:
    A/C switch can operate A/C normally.



NG
Go to step 2
OK

REPLACE No. 2 AIR CONDITIONING AMPLIFIER ASSEMBLY (A/C ECU) 

2.CHECK WIRE HARNESS (No. 2 AIR CONDITIONING AMPLIFIER ASSEMBLY (A/C ECU) - BATTERY AND BODY GROUND)
B109178E06

  1. Disconnect the L52 ECU connector.

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

    Standard voltage:
    Tester Connection
    		Condition
    		Specified Condition
    L52-21 (IG+) - Body ground
    		Engine switch on (IG)
    		10 to 14 V
    L52-1 (B) - Body ground
    		Always
    		10 to 14 V

    Standard resistance:
    Tester Connection
    		Condition
    		Specified Condition
    L52-20 (GND) - Body ground
    		Always
    		Below 1 Ω



NG
REPAIR OR REPLACE HARNESS AND CONNECTOR
OK


3.CHECK RESISTANCE OF COMMUNICATION LINE

E109775E04

  1. Disconnect the L52 ECU connector.

  1. Disconnect the L12 panel connector.

  1. Disconnect the L44 sensor connector.

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

    Standard resistance:
    Tester Connection
    		Specified Condition
    L52-30 (MPX+) - L44-22 (MPX2)
    		Below 1 Ω
    L52-31 (MPX-) - L12-8 (MPX2)
    		Below 1 Ω

    Result:
    Result
    		Proceed to
    Both are OK
    		A
    One is OK
    		B
    Both are NG
    		C



B
REPLACE No. 2 AIR CONDITIONING AMPLIFIER ASSEMBLY AND HARNESS AND CONNECTOR

C
REPAIR OR REPLACE HARNESS AND CONNECTOR
A

REPLACE No. 2 AIR CONDITIONING AMPLIFIER ASSEMBLY (A/C ECU)