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DTC    B156C    Extension Module Disconnected

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DESCRIPTION

The extension module and the radio and display receiver assembly are connected by the AVC-LAN communication line.
When an AVC-LAN communication error occurs between the extension module and the radio and display receiver assembly, this DTC will be stored.

DTC No.
DTC Detection Condition
Trouble Area
B156C*1
When either condition below is met:
  1. Extension module is/was not connected while the power switch is/was on (ACC or IG).
  2. Communication between the master unit and the extension module is not possible when the engine is/was started.
  1. Extension module power source circuit
  2. AVC-LAN circuit between radio and display receiver assembly and extension module
  3. Extension module
  4. Radio and display receiver assembly
  5. Harness or connector

HINT:
  1. *1: Even if no fault is present, this DTC may be stored depending on the auxiliary battery condition or engine start voltage.
  2. The radio and display receiver assembly is the master unit.


WIRING DIAGRAM


E226303E07


INSPECTION PROCEDURE

1.CHECK OPTIONAL COMPONENTS (INCLUDING ASSOCIATED WIRING)

  1. Check for optional components.

    1. Check that optional components (including associated wiring) which generate radio waves are not installed.

      Result:
      Result
      		Proceed to
      Optional components (including associated wiring) are installed.
      		A
      Optional components (including associated wiring) are not installed.
      		B

      HINT:
      1. Electrical noise from radio waves generated by optional components or the wiring for those components may affect AVC-LAN communication.
      2. This DTC may be stored when an AVC-LAN communication error occurs due to electrical noise.



B
Go to step 3
A


2.REMOVE OPTIONAL COMPONENTS (INCLUDING ASSOCIATED WIRING)

  1. Remove optional components (including associated wiring).

    NOTICE:
    Do not remove optional components or associated wiring without the permission of the customer.


NEXT


3.CHECK DTC

  1. Clear the DTCs (Click here).

  1. Recheck for DTCs and check if the same DTC is output again.

    OK:
    No DTCs are output.



NG
Go to step 4
OK

END 

4.CHECK HARNESS AND CONNECTOR (EXTENSION MODULE POWER SOURCE)

  1. Disconnect the extension module connector.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    z21-32 (E) - Body ground
    		Always
    		Below 1 Ω

  1. Measure the voltage according to the value(s) in the table below.

    Standard Voltage:
    Tester Connection
    		Condition
    		Specified Condition
    z21-16 (B+) - z21-32 (E)
    		Power switch off
    		11 to 14 V
    z21-11 (ACC) - z21-32 (E)
    		Power switch on (ACC)
    		11 to 14 V



NG
Go to step 7
OK


5.CHECK HARNESS AND CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY - EXTENSION MODULE)

  1. Disconnect the radio and display receiver assembly connector.

  1. Disconnect the extension module connector.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    z21-2 (AVC+) - z22-9 (AVC+)
    		Always
    		Below 1 Ω
    z21-3 (AVC-) - z22-10 (AVC-)
    		Always
    		Below 1 Ω
    z21-2 (AVC+) - Body ground
    		Always
    		10 kΩ or higher
    z21-3 (AVC-) - Body ground
    		Always
    		10 kΩ or higher



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


6.REPLACE EXTENSION MODULE

  1. Replace the extension module (Click here).

  1. Clear the DTCs (Click here).

  1. Recheck for DTCs and check if the same DTC is output again.

    OK:
    No DTCs are output.



NG
REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY (Click here)
OK

END 

7.CHECK HARNESS AND CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY - EXTENSION MODULE)

  1. Disconnect the radio and display receiver assembly connector.

  1. Disconnect the extension module connector.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    z21-11 (ACC) - z23-13 (ACC)
    		Always
    		Below 1 Ω
    z21-16 (B+) - z23-1 (B+)
    		Always
    		Below 1 Ω
    z21-32 (E) - z23-14 (E)
    		Always
    		Below 1 Ω
    z21-11 (ACC) - Body ground
    		Always
    		10 kΩ or higher
    z21-16 (B+) - Body ground
    		Always
    		10 kΩ or higher
    z21-32 (E) - Body ground
    		Always
    		10 kΩ or higher



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY (Click here)