DTC    B1249    Double Locking ECU Communication Stop

for Preparation Click here


DESCRIPTION

The main body ECU stores a DTC when communication with the double lock door control relay assembly is interrupted for 10 seconds or more.

DTC No.
DTC Detection Condition
Trouble Area
B1249
Communication between double lock door control relay assembly and main body ECU interrupted for 10 seconds or more, or communication wire malfunction.
  1. Harness or connector
  2. Double lock door control relay assembly
  3. Main body ECU

WIRING DIAGRAM


E176063E01


INSPECTION PROCEDURE

HINT:
  1. 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.
  2. When the main body ECU has been replaced with a new part, or when the battery negative terminal is reconnected, the ignition switch condition will be ON. Also, when the battery has been removed and installed, the condition will be the same as it was before the battery was disconnected.

NOTICE:
Inspect the fuses for circuits related to this system before performing the following 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 B1249 is output
    A
    DTC B1249 and B2325 are output
    B

    HINT:
    When both B1249 and B2325 are output at the same time, troubleshoot B2325 first.



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


3.CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL J/B - DOUBLE LOCK DOOR RELAY)


    E176064E01
  1. Disconnect the 3C instrument panel junction block assembly connector.

  1. Disconnect the D40 double lock door control relay assembly connector.

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

    Standard Resistance:
    Tester Connection
    Condition
    Specified Condition
    3C-27 (LIN2) - D40-9 (MPX1)
    Always
    Below 1 Ω
    D40-9 (MPX1) - Body ground
    Always
    10 kΩ or higher

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

    Standard Voltage:
    Tester Connection
    Condition
    Specified Condition
    D40-9 (MPX1) - Body ground
    Always
    Below 0.5 V

    Text in Illustration 
    *1
    Front view of wire harness connector
    (to Instrument Panel Junction Block Assembly)
    *2
    Front view of wire harness connector
    (to Double Lock Door Control Relay Assembly)

  1. Reconnect the instrument panel junction block assembly connector.

  1. Reconnect the double lock door control relay assembly connector.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


4.CHECK HARNESS AND CONNECTOR (DOUBLE LOCK DOOR RELAY - BATTERY AND BODY GROUND)


    E176065E01
  1. Disconnect the D40 double lock door control relay assembly connector.

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

    Standard Resistance:
    Tester Connection
    Condition
    Specified Condition
    D40-14 (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
    D40-1 (+B) - Body ground
    Always
    11 to 14 V

    Text in Illustration 
    *1
    Front view of wire harness connector
    (to Double Lock Door Control Relay Assembly)

  1. Reconnect the double lock door control relay assembly connector.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


5.REPLACE DOUBLE LOCK DOOR CONTROL RELAY ASSEMBLY NORMAL ONE
  1. Replace the double lock door control relay assembly with a normally functioning part (Click here).

  1. Clear DTCs (Click here).


NEXT


6.RECONFIRM DTC OUTPUT
  1. Recheck for DTCs (Click here).
    Result 
    Result
    Proceed to
    DTC B1249 is not output
    A
    DTC B1249 is output
    B



B
Go to step 7
A

END (DOUBLE LOCK DOOR CONTROL RELAY ASSEMBLY MALFUNCTION) 

7.INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

E176066E01


Text in Illustration 
*1
Component without harness connected
(Instrument Panel Junction Block Assembly)
  1. Remove the instrument panel junction block assembly (Click here).

  1. Remove the main body ECU from instrument panel junction block assembly (Click here).

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

    Standard Resistance:
    Tester Connection
    Condition
    Specified Condition
    3C-27 (LIN2) - 3F-16 (LIN2)
    Always
    Below 1 Ω
    3C-27 (LIN2) - Body ground
    Always
    10 kΩ or higher

  1. Reinstall the main body ECU (Click here).

  1. Reinstall the instrument panel junction block assembly (Click here).



NG
REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY (Click here)
OK

REPLACE MAIN BODY ECU (Click here)