DTC B2789 No Response from ID BOX |
| DTC No. | DTC Detection Condition | Trouble Area |
| B2789 | No communication between certification ECU and ID code box for 10 seconds or more. |
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| 1.CLEAR DTC |
Clear DTCs (Click here).
| NEXT | |
| 2.CHECK FOR DTC |
Check for DTCs (Click here).
| Result | Proceed to |
| DTC B2789 is output | A |
| DTC B2789 and B2785 are output | B |
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| A | |
| 3.CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - ID CODE BOX) |
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Disconnect the D34 certification ECU connector.
Disconnect the D30 ID code box connector.
Measure the resistance and voltage according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
| D34-29 (LIN) - D30-3 (LIN1) | Always | Below 1 Ω |
| D34-29 (LIN) - Body ground | Always | 10 kΩ or higher |
| Tester Connection | Condition | Specified Condition |
| D34-29 (LIN) - Body ground | Always | Below 0.5 V |
| *1 | Front view of wire harness connector (to Certification ECU) |
| *2 | Front view of wire harness connector (to ID Code Box) |
Reconnect the certification ECU connector.
Reconnect the ID code box connector.
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| OK | |
| 4.CHECK HARNESS AND CONNECTOR (ID CODE BOX - BATTERY AND BODY GROUND) |
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Disconnect the D30 ID code box connector.
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
| D30-8 (GND) - Body ground | Always | Below 1 Ω |
Measure the voltage according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
| D30-1 (+B) - Body ground | Always | 11 to 14 V |
| *1 | Front view of wire harness connector (to ID Code Box) |
Reconnect the ID code box connector.
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| OK | |
| 5.REPLACE ID CODE BOX NORMAL ONE |
Replace the ID code box with a normally functioning part (Refer to the Service Bulletin).
Clear DTCs (Click here).
| NEXT | |
| 6.RECHECK FOR DTC |
Recheck for DTCs (Click here).
| Result | Proceed to |
| DTC B2789 is not output | A |
| DTC B2789 is output | B |
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| A | ||
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