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.
DTC No. |
Detection Item |
DTC Detection Condition |
Trouble Area |
Note |
---|---|---|---|---|
B279A |
Theft Deterrent System Communication Line High Fixation |
Communication line (EFIO-IMI) between the ECM and transponder key ECU assembly is stuck high. |
|
|
Vehicle Condition when Malfunction Detected |
Fail-safe Operation when Malfunction Detected |
---|---|
Engine cannot be started (initial ignition occurs and engine cranks, then ignition stops) |
Engine cannot be started |
DTC No. |
Data List and Active Test |
---|---|
B279A |
- |
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
Click here
PROCEDURE
1. |
CLEAR DTC |
(a) Clear the DTCs.
Powertrain > Engine and ECT > Clear DTCs
|
2. |
CHECK FOR DTC |
(a) Check for DTCs.
Powertrain > Engine and ECT > Trouble CodesHINT:
Before checking for DTCs, perform the "DTC Output Confirmation Operation" procedure.
OK:
DTC B279A is not output.
Result |
Proceed to |
---|---|
B279A is not output |
A |
B279A is output |
B |
A | ![]() |
USE SIMULATION METHOD TO CHECK |
|
3. |
CHECK CONNECTION OF CONNECTOR |
(a) Check that the connectors are properly connected to the ECM and transponder key ECU assembly.
OK:
Connectors are properly connected.
NG | ![]() |
CONNECT CONNECTORS PROPERLY |
|
4. |
CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU ASSEMBLY - ECM AND BODY GROUND) |
(a) Disconnect the F22 transponder key ECU assembly connector
(b) Disconnect the A38 ECM connector
(c) Measure the resistance according to the value(s) in the table below
Standard Resistance:
Tester Connection |
Condition |
Specified Condition |
---|---|---|
F22-13 (EFIO) - A38-28 (IMI) |
Always |
Below 1 Ω |
F22-13 (EFIO) - Body ground |
Always |
10 kΩ or higher |
A38-28 (IMI) - Body ground |
Always |
10 kΩ or higher |
NG | ![]() |
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
5. |
REPLACE TRANSPONDER KEY ECU ASSEMBLY |
(a) Replace the transponder key ECU assembly with a new one.
Click here
|
6. |
CLEAR DTC |
(a) Clear the DTCs.
Powertrain > Engine and ECT > Clear DTCs
|
7. |
CHECK FOR DTC |
(a) Check for DTCs.
Powertrain > Engine and ECT > Trouble CodesHINT:
Before checking for DTCs, perform the "DTC Output Confirmation Operation" procedure.
OK:
DTC B279A is not output.
Result |
Proceed to |
---|---|
B279A is not output |
A |
B279A is output |
B |
A | ![]() |
END (TRANSPONDER KEY ECU ASSEMBLY WAS DEFECTIVE) |
B | ![]() |
REPLACE ECM |
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