B279A

ENGINE IMMOBILISER: ENGINE IMMOBILISER SYSTEM (w/o Smart Key System): B279A: Theft Deterrent System Communication Line High Fixation
B279A - Theft Deterrent System Communication Line High Fixation

DESCRIPTION

If the communication line (EFIO-IMI) to the transponder key ECU assembly is stuck high (e.g. shorted to +B), the ECM stores this DTC.





WIRING DIAGRAM





INSPECTION PROCEDURE

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

PROCEDURE

1. CHECK DTC OUTPUT

(a) Recheck for DTCs Engine Immobiliser System (w/o Smart Key System).

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

Result:





B -- GO TO DTC CHART Engine Immobiliser System (w/o Smart Key System)
A -- 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 TRANSPONDER KEY ECU ASSEMBLY (OUTPUT)

(a) Reconnect the transponder key ECU assembly connector.

(b) Reconnect the ECM connector.

(c) Using an oscilloscope, check the waveform.





Waveform 1 (Reference):





Text in Illustration





NG -- REPLACE TRANSPONDER KEY ECU ASSEMBLY

OK -- REPLACE ECM Removal

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 Immobiliser System (W/O Smart Key System).

NEXT -- Continue to next step.

6. REGISTER ECU COMMUNICATION ID

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

NEXT -- Continue to next step.

7. CHECK DTC OUTPUT

(a) Clear the DTCs Engine Immobiliser System (w/o Smart Key System).

(b) Recheck for DTCs.

OK:

DTC B279A is not output.

NG -- REPLACE ECM Removal

OK -- END (TRANSPONDER KEY ECU WAS DEFECTIVE)