Engine Immobilizer System (w/o Smart Key System)
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 Immobilizer System (w/o Smart Key System).
* If the ECM is replaced, register the ECU communication ID Engine Immobilizer System (w/o Smart Key System).
PROCEDURE
1. CHECK DTC OUTPUT
(a) Recheck for DTCs Engine Immobilizer 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 Immobilizer 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:
for 2GR-FE
for 1AR-FE
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):
OK:
Waveform is output normally (see illustration).
Result:
Text in Illustration
B -- REPLACE ECM Removal
C -- REPLACE ECM Removal
A -- 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 Immobilizer System (w/o Smart Key System).
NEXT -- Continue to next step.
6. REGISTER ECU COMMUNICATION ID
(a) Register the ECU communication ID Engine Immobilizer System (w/o Smart Key System).
NEXT -- Continue to next step.
7. CHECK DTC OUTPUT
(a) Clear the DTCs Engine Immobilizer System (w/o Smart Key System).
(b) Recheck for DTCs.
OK:
DTC B279A is not output.
Result:
B -- REPLACE ECM Removal
C -- REPLACE ECM Removal
A -- END (TRANSPONDER KEY ECU WAS DEFECTIVE)