Engine Immobilizer System (w/ Smart Key System)

THEFT DETERRENT / KEYLESS ENTRY: ENGINE IMMOBILISER SYSTEM (w/ Smart Key System): B279A: Theft Deterrent System Communication Line High Fixation
B279A - Theft Deterrent System Communication Line High Fixation

DESCRIPTION

When the communication line (IMI - EFIO) between the ECM and ID code box (immobiliser code ECU) is stuck on HI output, the ECM stores this DTC.





* *: Only output while a malfunction is present.

Vehicle Condition and Fail-safe Operation when Malfunction Detected





Related Data List and Active Test





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
* When replacing the ID code box (immobiliser code ECU), refer to Registration Engine Immobilizer System (w/ Smart Key System).
* The fixed 12 V power source voltage in the ECM is output through a resistance from terminal IMI. The ID code box (immobiliser code ECU) grounds or does not ground this power source voltage accordingly.
* After performing repairs, perform the operation that fulfills the DTC output confirmation operation, and then confirm that no DTCs are output again.

HINT
When DTC B279A and the certification ECU (smart key ECU assembly) DTC are output simultaneously, first perform troubleshooting for the certification ECU (smart key ECU assembly) DTC.

PROCEDURE

1. CLEAR DTC

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

NEXT -- Continue to next step.

2. CHECK FOR DTC

(a) Turn the engine switch on (IG) and wait 10 seconds.

(b) Check for DTCs Engine Immobilizer System (w/ Smart Key System).

Result





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

B -- Go to DIAGNOSTIC TROUBLE CODE CHART Engine Immobilizer System (W/ Smart Key System)
A -- Continue to next step.

3. CHECK CONNECTION OF CONNECTOR

(a) Turn the engine switch off.

(b) Check that the connectors are properly connected to the ECM and ID code box (immobiliser code ECU).

OK:

Connectors are properly connected.

NG -- CONNECT CONNECTORS PROPERLY
OK -- Continue to next step.

4. CHECK HARNESS AND CONNECTOR (ID CODE BOX - ECM)

(a) Disconnect the C38 ID code box (immobiliser code ECU) connector.

(b) Disconnect the A35 ECM connector.

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

Standard Resistance:





(d) Measure the voltage according to the value(s) in the table below.

Standard Voltage:





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

5. REPLACE ID CODE BOX (IMMOBILISER CODE ECU)

(a) Replace the ID code box (immobiliser code ECU) with a new one Removal.

NEXT -- Continue to next step.

6. CLEAR DTC

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

NEXT -- Continue to next step.

7. REGISTER RECOGNITION CODES

(a) Register the recognition codes in the ECUs Engine Immobilizer System (w/ Smart Key System).

NEXT -- Continue to next step.

8. REGISTER ECU COMMUNICATION ID (ID CODE BOX - ECM)

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

NEXT -- Continue to next step.

9. CHECK FOR DTC

(a) Check for DTCs Engine Immobilizer System (w/ Smart Key System).

HINT
Before checking for DTCs, perform the "DTC Output Confirmation Operation" procedure.

OK:

DTC B279A is not output.

NG -- REPLACE ECM Removal

OK -- END (ID CODE BOX [IMMOBILISER CODE ECU] IS DEFECTIVE)