DTC B2287 LIN Communication Master Malfunction |
DTC B278C Lost Communication with Power Source Control |
| DTC No. | DTC Detection Condition | Trouble Area |
| B2287 | Communication malfunction between the certification ECU and the power management control ECU*1 or the power source control ECU*2 |
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| B278C | Communication between certification ECU and the power management control ECU*1 or the power source control ECU*2 interrupted for 10 seconds or more |

| 1.CLEAR DTC |
Clear DTCs (Click here).
| NEXT | |
| 2.READ OUTPUT DTC |
Check for DTCs (Click here).
| Result | Proceed to |
| DTC B2287 and/or B278C are output | A |
| B2287 and/or B278C and B2785 are output | B |
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| A | |
| 3.SYSTEM CHECK |
Check the vehicle specifications.
| Result | Proceed to |
| for 1KR-FE and 1NR-FE with Entry and Start System | A |
| for 1ND-TV with Entry and Start System | B |
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| A | |
| 4.CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - POWER MANAGEMENT CONTROL ECU) |
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Disconnect the D34 certification ECU connector.
Disconnect the D38 power management control ECU connector.
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
| D34-29 (LIN) - D38-24 (LIN2) | Always | Below 1 Ω |
| D38-24 (LIN2) - Body ground | Always | 10 KΩ or higher |
Measure the voltage according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
| D38-24 (LIN2) - 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 Power Management Control ECU) |
Reconnect the certification ECU connector.
Reconnect the power management control ECU connector.
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| OK | |
| 5.CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - BATTERY AND BODY GROUND) |
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Disconnect the D38 power management control ECU connector.
Measure the voltage according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
| D38-1 (AM22) - Body ground | Always | 11 to 14 V |
| D38-2 (AM21) - Body ground | Always | 11 to 14 V |
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
| D38-6 (GND) - Body ground | Always | Below 1 Ω |
| D38-5 (GND2) - Body ground | Always | Below 1 Ω |
| *1 | Front view of wire harness connector (to Power Management Control ECU) |
Reconnect the power management control ECU connector.
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| OK | |
| 6.REPLACE POWER MANAGEMENT CONTROL ECU NORMAL ONE |
Replace the power management control ECU with a normally functioning part (Click here).
Clear DTCs (Click here).
| NEXT | |
| 7.RECONFIRM DTC OUTPUT |
Recheck for DTCs (Click here).
| Result | Proceed to |
| DTC B2287 and/or B278C are not output | A |
| DTC B2287 and/or B278C are output | B |
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| A | ||
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| 8.CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - POWER SOURCE CONTROL ECU) |
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Disconnect the D34 certification ECU connector.
Disconnect the D73 power source control ECU connector.
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
| D34-29 (LIN) - D73-24 (LIN2) | Always | Below 1 Ω |
| D73-24 (LIN2) - Body ground | Always | 10 KΩ or higher |
Measure the voltage according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
| D73-24 (LIN2) - 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 Power Source Control ECU) |
Reconnect the certification ECU connector.
Reconnect the power source control ECU connector.
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| OK | |
| 9.CHECK HARNESS AND CONNECTOR (POWER SOURCE CONTROL ECU - BATTERY AND BODY GROUND) |
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Disconnect the D73 power source control ECU connector.
Measure the voltage according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
| D73-1 (AM22) - Body ground | Always | 11 to 14 V |
| D73-2 (AM21) - Body ground | Always | 11 to 14 V |
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
| D73-6 (GND) - Body ground | Always | Below 1 Ω |
| D73-5 (GND2) - Body ground | Always | Below 1 Ω |
| *1 | Front view of wire harness connector (to Power source Control ECU) |
Reconnect the power source control ECU connector.
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| OK | |
| 10.REPLACE POWER SOURCE CONTROL ECU NORMAL ONE |
Replace the power source control ECU with a normally functioning part (Click here).
Clear DTCs (Click here).
| NEXT | |
| 11.RECONFIRM DTC OUTPUT |
Recheck for DTCs (Click here).
| Result | Proceed to |
| DTC B2287 and/or B278C are not output | A |
| DTC B2287 and/or B278C are output | B |
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| A | ||
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