DESCRIPTION
If the communication line (IMI - EFIO) between the ECM and ID code box (immobiliser code ECU) is stuck high, the ECM will store this DTC.
DTC No. |
Detection Item |
DTC Detection Condition |
Trouble Area |
Note |
---|---|---|---|---|
B279A |
Theft Deterrent System Communication Line High Fixation |
The communication line (IMI - EFIO) between the ECM and ID code box (immobiliser code ECU) is stuck high. (1 trip detection logic*) |
|
DTC output confirmation operation:
|
Vehicle Condition when Malfunction Detected |
Fail-safe Operation when Malfunction Detected |
---|---|
Engine cannot be started |
Engine cannot be started |
DTC No. |
Data List and Active Test |
---|---|
B279A |
- |
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
Click here
HINT:
When DTC B279A and a 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.
Click here
|
2. |
CHECK FOR DTC |
(a) Turn the engine switch on (IG) and wait 10 seconds.
(b) Check for DTCs.
Click here
HINT:
If DTCs other than DTC B279A are output, troubleshoot those DTCs first.
Result |
Proceed to |
---|---|
Only DTC or B279A is output |
A |
DTC or B279A and other DTCs are output |
B |
B | ![]() |
GO TO DIAGNOSTIC TROUBLE CODE CHART |
|
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 |
|
4. |
CHECK HARNESS AND CONNECTOR (ID CODE BOX (IMMOBILISER CODE ECU) - ECM) |
(a) Disconnect the F21 ID code box (immobiliser code ECU) 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 |
---|---|---|
F21-4 (EFIO) - A38-28 (IMI) |
Always |
Below 1 Ω |
F21-4 (EFIO) or A38-28 (IMI) - Body ground |
Always |
10 kΩ or higher |
NG | ![]() |
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
5. |
REPLACE ID CODE BOX (IMMOBILISER CODE ECU) |
(a) Replace the ID code box (immobiliser code ECU) with a new one.
Click here
|
6. |
REGISTER RECOGNITION CODE |
(a) Register the recognition codes in the ECUs.
Click here
|
7. |
REGISTER ECU COMMUNICATION ID |
(a) Register the ECU communication ID.
Click here
|
8. |
CHECK WHETHER ENGINE STARTS |
(a) Check that the engine starts.
OK:
Engine starts normally.
NG | ![]() |
REPLACE ECM |
|
9. |
CLEAR DTC |
(a) Clear the DTCs.
Click here
|
10. |
CHECK FOR DTC |
(a) Perform "DTC Output Confirmation Operation" procedure.
(b) Check for DTCs.
Click here
OK:
DTC B279A is not output.
OK | ![]() |
END (ID CODE BOX (IMMOBILISER CODE ECU) WAS DEFECTIVE) |
NG | ![]() |
REPLACE ECM |
Toyota CH-R Service Manual > Meter / Gauge System: Data List / Active Test
DATA LIST / ACTIVE TEST
DATA LIST
NOTICE:
In the table below, the values listed under "Normal Condition" are reference
values. Do not depend solely on these reference values when deciding whether a part
is faulty or not.
HINT:
Using the Techstream to read the Data List allows the ...
Toyota CH-R Service Manual > Vehicle Stability Control System: Stop Light Switch OFF Stuck Malfunction (C1426)
DESCRIPTION
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