DTC B279A Theft Deterrent System Communication Line High Fixation |
| DTC No. | DTC Detection Condition | Trouble Area |
| B279A | When communication line (EFIO - IMI) between ECM and ID code box is stuck on HI output. |
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| 1.CHECK FOR DTC |
Clear the DTCs (Click here).
Recheck for DTCs (Click here).
| Result | Proceed to |
| DTC B279A is output | A |
| DTC B279A and other DTCs are output | B |
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| A | |
| 2.CHECK HARNESS AND CONNECTOR (ID CODE BOX - ECM) |
Disconnect the ID code box connector.
Disconnect the ECM connector.

| *1 | Front view of wire harness connector (to ID Code Box) | *2 | Front view of wire harness connector (to ECM) |
| *3 | for 1KR-FE and 1NR-FE | *4 | for 1ND-TV |
Measure the resistance according to the value(s) in the table below.
for 1ND-TV
| Tester Connection | Condition | Specified Condition |
| D30-6 (EFIO) - A19-77 (IMI) | Always | Below 1 Ω |
| D30-6 (EFIO) - Body ground | Always | 10 kΩ or higher |
for 1KR-FE and 1NR-FE
| Tester Connection | Condition | Specified Condition |
| D30-6 (EFIO) - A18-11 (IMI) | Always | Below 1 Ω |
| D30-6 (EFIO) - Body ground | Always | 10 kΩ or higher |
Measure the voltage according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
| D30-6 (EFIO) - Body ground | Always | Below 1 V |
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| OK | |
| 3.CHECK ID CODE BOX (WAVEFORM) |
Reconnect the ID code box connector.
Reconnect the ECM connector.
Using an oscilloscope, check the waveform.

| *1 | Component with harness connected (ID Code Box) |
| Item | Content |
| Terminal No. (Symbol) | D30-6 (EFIO) - D30-8 (GND) |
| Tool Setting | 5 V/DIV., 100 msec./DIV. |
| Condition | Engine switch on (IG) |
| Result | Proceed to |
| Waveform is not output normally | A |
| Waveform is output normally (for 1ND-TV) | B |
| Waveform is output normally (for 1KR-FE) | C |
| Waveform is output normally (for 1NR-FE) | D |
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| A | |
| 4.REPLACE ID CODE BOX |
Replace the ID code box.
| NEXT | |
| 5.ECU CODE REGISTRATION |
Register the ECU code.
| NEXT | |
| 6.REGISTER ECU COMMUNICATION ID |
Register the ECU communication ID.
| NEXT | |
| 7.CHECK DTC OUTPUT |
Clear the DTCs (Click here).
Recheck for DTCs (Click here).
| Result | Proceed to |
| DTC B279A is not output | A |
| DTC B279A is output (for 1ND-TV) | B |
| DTC B279A is output (for 1KR-FE) | C |
| DTC B279A is output (for 1NR-FE) | D |
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| A | ||
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