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Engine Immobilizer System (W/O Smart Key System)





THEFT DETERRENT / KEYLESS ENTRY: ENGINE IMMOBILISER SYSTEM (w/o Smart Key System): B279A; Theft Deterrent System Communication Line High Fixation; 2013 MY Corolla [07/2012 -]
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.





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
* If the transponder key ECU assembly is replaced, register the key and ECU communication ID Engine Immobilizer System (W/O Smart Key System).
* If the ECM is replaced, register the ECU communication ID Engine Immobilizer System (W/O Smart Key System).

PROCEDURE

1. CHECK DTC OUTPUT

(a) Recheck for DTCs Engine Immobilizer System (W/O Smart Key System).

HINT
If any DTCs other than DTC B279A are output, troubleshoot those DTCs first.

Result:





A -- GO TO DTC CHART Engine Immobilizer System (W/O Smart Key System)
B -- Continue to next step.

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

(a) Disconnect the transponder key ECU assembly connector.

(b) Disconnect the ECM connector.





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

Standard Resistance:





Standard Voltage:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

3. CHECK ECM (INPUT)

(a) Reconnect the transponder key ECU assembly connector.

(b) Reconnect the ECM connector.

(c) Measure the waveform.





Waveform 1 (Reference):





* *1: for 2AZ-FE

* *2: for 2ZR-FE

Result:





A -- REPLACE ECM Removal

B -- REPLACE ECM Removal
C -- Continue to next step.

4. REPLACE TRANSPONDER KEY ECU ASSEMBLY

(a) Replace the transponder key ECU assembly Removal.

NEXT -- Continue to next step.

5. REGISTER KEY

(a) Register the key Engine Immobilizer System (W/O Smart Key System).

NEXT -- Continue to next step.

6. REGISTER ECU COMMUNICATION ID

(a) Register the ECU communication ID Engine Immobilizer System (W/O Smart Key System).

NEXT -- Continue to next step.

7. CHECK DTC OUTPUT

(a) Clear the DTCs Engine Immobilizer System (W/O Smart Key System).

(b) Recheck for DTCs.

OK:

B279A is not reoutput.

Result:





A -- REPLACE ECM Removal

B -- REPLACE ECM Removal

C -- END (TRANSPONDER KEY ECU IS DEFECTIVE)