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
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 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:

A -- GO TO DTC CHART Engine Immobiliser 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.

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):

Result:

B -- REPLACE ECM Removal

A -- 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 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:

B279A is not reoutput.

Result:

B -- REPLACE ECM Removal

A -- REPLACE ECM Removal

C -- END (TRANSPONDER KEY ECU IS DEFECTIVE)