Dtc B279A Theft Deterrent System Communication Line High Fixation

Vehicle Interior. Corolla. Zre142 Aze141
Theft Deterrent Keyless Entry. Corolla. Zre142 Aze141

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK DTC OUTPUT

CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU - ECM)

CHECK ECM (INPUT)

REPLACE TRANSPONDER KEY ECU ASSEMBLY

REGISTER KEY

REGISTER ECU COMMUNICATION ID

CHECK DTC OUTPUT

DTC B279A Theft Deterrent System Communication Line High Fixation


DESCRIPTION

If the communication line (EFIO-IMI) to the transponder key ECU assembly is stuck on HI output, the ECM outputs this DTC.

DTC No.
DTC Detection Condition
Trouble Area
B279A
Communication line (EFIO-IMI) between ECM and the transponder key ECU assembly is stuck on HI output
  1. Wire harness or connector
  2. Transponder key ECU assembly
  3. ECM

WIRING DIAGRAM


Corolla. Zre142 Aze141.Theft Deterrent Keyless Entry.Smart Key System (For Entry Function). Dtc B279A Theft Deterrent System Communication Line High Fixation


INSPECTION PROCEDURE

NOTICE:
  1. If the transponder key ECU assembly is replaced, register the key and ECU communication ID (COROLLA_ZRE142 RM00000120Y02CX.html).
  2. If the ECM is replaced, register the ECU communication ID (COROLLA_ZRE142 RM00000120Y02CX.html).
1.CHECK DTC OUTPUT

  1. Recheck for DTCs (COROLLA_ZRE142 RM000001GV807PX.html).

    HINT:
    If any DTCs other than DTC B279A are output, troubleshoot those DTCs first.
    Result:
    Result
    		Proceed to
    DTC B279A and other DTCs reoutput
    		A
    DTC B279A reoutput
    		B


A
GO TO DTC CHART (COROLLA_ZRE142 RM00000292H03QX.html)
B


2.CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU - ECM)

  1. Disconnect the transponder key ECU assembly connector.



  1. Disconnect the ECM connector.


    Corolla. Zre142 Aze141.Theft Deterrent Keyless Entry.Smart Key System (For Entry Function). Dtc B279A Theft Deterrent System Communication Line High Fixation

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    E21-13 (EFIO) - A50-11 (IMI)
    		Always
    		Below 1 Ω
    E21-13 (EFIO) - Body ground
    		Always
    		10 kΩ or higher
    Standard Voltage:
    Tester Connection
    		Condition
    		Specified Condition
    E21-13 (EFIO) - Body ground
    		Always
    		Below 1 V


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


3.CHECK ECM (INPUT)

  1. Reconnect the transponder key ECU assembly connector.

  1. Reconnect the ECM connector.



  1. Measure the waveform.


    Corolla. Zre142 Aze141.Theft Deterrent Keyless Entry.Smart Key System (For Entry Function). Dtc B279A Theft Deterrent System Communication Line High Fixation

    Waveform 1 (Reference):
    Item
    		Content
    Terminal No. (Symbols)
    		A50-11 (IMI) - B31-104 (E1)*1
    A50-11 (IMI) - B31-105 (E1)*2
    Tool Setting
    		2 V/DIV., 1 s./DIV.
    Condition
    		Ignition switch ON
    1. *1: for 2AZ-FE
    2. *2: for 2ZR-FE
    Result:
    Result
    		Proceed to
    OK (for 2ZR-FE)
    		A
    OK (for 2AZ-FE)
    		B
    NG
    		C


A
REPLACE ECM (COROLLA_ZRE142 RM000001CN0030X.html)

B
REPLACE ECM (COROLLA_ZRE142 RM000002WT506MX.html)
C


4.REPLACE TRANSPONDER KEY ECU ASSEMBLY

  1. Replace the transponder key ECU assembly (COROLLA_ZRE142 RM000003G05004X.html).


NEXT


5.REGISTER KEY

  1. Register the key (COROLLA_ZRE142 RM00000120Y02CX.html).


NEXT


6.REGISTER ECU COMMUNICATION ID

  1. Register the ECU communication ID (COROLLA_ZRE142 RM00000120Y02CX.html).


NEXT


7.CHECK DTC OUTPUT

  1. Clear the DTCs (COROLLA_ZRE142 RM000001GV807PX.html).

  1. Recheck for DTCs.

    OK:
    B279A is not reoutput.
    Result:
    Result
    		Proceed to
    NG (for 2ZR-FE)
    		A
    NG (for 2ZA-FE)
    		B
    OK
    		C


A
REPLACE ECM (COROLLA_ZRE142 RM000001CN0030X.html)

B
REPLACE ECM (COROLLA_ZRE142 RM000002WT506MX.html)
C

END (TRANSPONDER KEY ECU IS DEFECTIVE)