DTC    B1296    Front Light ECU Communication Stop

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DESCRIPTION

This DTC is detected when communication between the engine room No. 2 junction block (front controller) and gateway ECU stops for more than 10 seconds.

DTC No.
DTC Detection Condition
Trouble Area
B1296
Front controller communication stops
  1. Engine room No. 2 junction block (front controller)
  2. Wire harness

WIRING DIAGRAM


B111359E01


INSPECTION PROCEDURE

1.CHECK OPERATION

  1. Turn the headlight dimmer switch ON and check that the headlights illuminate.

    OK:
    Headlights illuminate.



NG
Go to step 2
OK

REPLACE ENGINE ROOM NO. 2 RELAY BLOCK (FRONT CONTROLLER) 

2.INSPECT FUSE (MPX-B, D/C CUT)

  1. Remove the MPX-B and D/C CUT fuses from the engine room No. 1 relay block, junction block.

  1. Measure the resistance of the fuses.

    Standard resistance:
    Below 1 Ω



NG
REPLACE FUSE
OK


3.CHECK WIRE HARNESS (ENGINE ROOM NO.2 R/B (FRONT CONTROLLER) - BATTERY AND BODY GROUND)

E109777E03

  1. Disconnect the 2F and 2E relay block controllers from the engine room No. 2 relay block, junction block.

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

    Standard voltage:
    Tester Connection
    		Specified Condition
    2E-4 (FMB3) - Body ground
    		10 to 14 V

    Standard resistance:
    Tester Connection
    		Specified Condition
    2F-1 (E) - Body ground
    		Below 1 Ω



NG
REPAIR OR REPLACE HARNESS AND CONNECTOR
OK


4.CHECK RESISTANCE OF COMMUNICATION LINE

E109776E05

  1. Disconnect the L22 switch connector.

  1. Disconnect the A32 or A31 ECU connector.

  1. Disconnect the 2F controller from the engine room relay block No. 2.

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

    Standard resistance:
    Tester Connection
    		Specified Condition
    2F-5 (MPX1) - L22-7 (MPX2)
    		Below 1 Ω
    2F-6 (MPX2) - A32-6 (MPX4)
    		Below 1 Ω
    2F-6 (MPX2) - A31-6 (MPX1)
    		Below 1 Ω

    Result:
    Result
    		Proceed to
    All are OK
    		A
    One or two is / are OK
    		B
    All are NG
    		C



B
REPLACE ENGINE ROOM NO. 2 RELAY BLOCK AND HARNESS AND CONNECTOR

C
REPAIR OR REPLACE HARNESS AND CONNECTOR
A


5.CHECK OPERATION OF FRONT CONTROLLER

  1. After replacing the front controller with a normally functioning controller, check that the headlights illuminate.

    OK:
    Headlights illuminate.



NG
REPLACE ENGINE ROOM NO. 2 RELAY BLOCK
OK

REPLACE FRONT CONTROLLER