B279A

ENGINE IMMOBILISER: ENGINE IMMOBILISER SYSTEM: B279A: Theft Deterrent System Communication Line High Fixation

DTC B279A - Theft Deterrent System Communication Line High Fixation

DESCRIPTION

If the communication line (EFIO-IMI) to the transponder key ECU is stuck on HI output, the ECM outputs this DTC.






WIRING DIAGRAM





INSPECTION PROCEDURE
HINT:
- If the transponder key ECU assembly is replaced, register the key and ECU communication ID.
- If the ECM is replaced, register the ECU communication ID.

PROCEDURE

1. CLEAR DTC
(a) Clear the DTC Reading and Clearing Diagnostic Trouble Codes.
NEXT -- Continue to next step.

2. CHECK FOR DTC
(a) Check for DTC Reading and Clearing Diagnostic Trouble Codes.

Result





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

B -- GO TO DIAGNOSTIC TROUBLE CODE CHART
A -- Continue to next step.

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




(a) Disconnect the T10 ECU connector.
(b) Disconnect the E14 ECM connector.
(c) Measure the resistance and voltage according to the value(s) in the table below.
Standard Resistance:






Standard Voltage:





(d) Reconnect the ECU and ECM connector.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

4. INSPECT TRANSPONDER KEY ECU (OUTPUT)




(a) Measure the waveform.






OK:
Waveform is output normally (see illustration).
NG -- REPLACE ECM
OK -- Continue to next step.

5. CHECK TRANSPONDER KEY ECU (POWER SOURCE AND BODY GROUND)




(a) Turn the ignition switch to ON.
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE TRANSPONDER KEY ECU