DTC    B2789    No Response from ID BOX

for Preparation Click here


DESCRIPTION

The certification ECU stores a DTC when communication with the ID code box is interrupted for more than a specified time.

DTC No.
DTC Detection Condition
Trouble Area
B2789
No communication between certification ECU and ID code box for 10 seconds or more.
  1. Harness or connector
  2. ID code box
  3. Certification ECU

WIRING DIAGRAM


E176060E01

HINT:
When using the intelligent tester, repeatedly turn either front door courtesy light switch off-and-on at intervals of 1.5 seconds or less, until communication between the intelligent tester and vehicle begins.

NOTICE:
  1. Inspect the fuses for this circuit before starting this inspection procedure.
  2. Refer to the Service Bulletin for the installation position of the certification ECU.


INSPECTION PROCEDURE

1.CLEAR DTC
  1. Clear DTCs (Click here).


NEXT


2.CHECK FOR DTC
  1. Check for DTCs (Click here).
    Result 
    Result
    Proceed to
    DTC B2789 is output
    A
    DTC B2789 and B2785 are output
    B

    HINT:
    When both B2789 and B2785 are output at the same time, troubleshoot B2785 first.



B
GO TO DIAGNOSTIC TROUBLE CODE CHART (Click here)
A


3.CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - ID CODE BOX)


    E176061E01
  1. Disconnect the D34 certification ECU connector.

  1. Disconnect the D30 ID code box connector.

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

    Standard Resistance:
    Tester Connection
    Condition
    Specified Condition
    D34-29 (LIN) - D30-3 (LIN1)
    Always
    Below 1 Ω
    D34-29 (LIN) - Body ground
    Always
    10 kΩ or higher

    Standard Voltage:
    Tester Connection
    Condition
    Specified Condition
    D34-29 (LIN) - Body ground
    Always
    Below 0.5 V

    Text in Illustration 
    *1
    Front view of wire harness connector
    (to Certification ECU)
    *2
    Front view of wire harness connector
    (to ID Code Box)

  1. Reconnect the certification ECU connector.

  1. Reconnect the ID code box connector.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


4.CHECK HARNESS AND CONNECTOR (ID CODE BOX - BATTERY AND BODY GROUND)


    E176062E01
  1. Disconnect the D30 ID code box connector.

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

    Standard Resistance:
    Tester Connection
    Condition
    Specified Condition
    D30-8 (GND) - 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
    D30-1 (+B) - Body ground
    Always
    11 to 14 V

    Text in Illustration 
    *1
    Front view of wire harness connector
    (to ID Code Box)

  1. Reconnect the ID code box connector.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


5.REPLACE ID CODE BOX NORMAL ONE
  1. Replace the ID code box with a normally functioning part (Refer to the Service Bulletin).

  1. Clear DTCs (Click here).


NEXT


6.RECHECK FOR DTC
  1. Recheck for DTCs (Click here).
    Result 
    Result
    Proceed to
    DTC B2789 is not output
    A
    DTC B2789 is output
    B



B
REPLACE CERTIFICATION ECU
A

END (ID CODE BOX MALFUNCTION)