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Engine Immobiliser 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
B279A - Theft Deterrent System Communication Line High Fixation

DESCRIPTION

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





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
* If the transponder key ECU 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 connector.

(b) Disconnect the ECM connector.

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

Standard Resistance:

for 2GR-FE





for 1AR-FE





Standard Voltage:





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

3. INSPECT TRANSPONDER KEY ECU (OUTPUT)

(a) Reconnect the transponder key ECU connector.

(b) Reconnect the ECM connector.

(c) Using an oscilloscope, check the waveform.





Waveform 1





Result





Text in Illustration





C -- REPLACE ECM Removal

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

4. REPLACE TRANSPONDER KEY ECU

(a) Replace the transponder key ECU 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 Engine Immobiliser System (w/o Smart Key System).

OK:

DTC B279A is not output.

Result





C -- REPLACE ECM Removal

B -- REPLACE ECM Removal

A -- END (TRANSPONDER KEY ECU WAS DEFECTIVE)