DTC B1211 Driver Door ECU Communication Stop |
| DTC No. | DTC Detection Condition | Trouble Area |
| B1211 | Multiplex network door ECU front LH communication stops |
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| 1.CHECK OPERATION |
Open the driver door and check that the door warning light (built into the combination meter) illuminates.
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| OK | ||
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| 2.CHECK WIRE HARNESS (MULTIPLEX NETWORK DOOR ECU FRONT LH (DOOR ECU LH) - BATTERY AND BODY GROUND) |
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Disconnect the O3 ECU connector.
Measure the voltage and resistance of the wire harness side connector.
| Tester Connection | Specified Condition |
| O3-4 (CPUB) - Body ground | 10 to 14 V |
| Tester Connection | Specified Condition |
| O3-1 (GND) - Body ground | Below 1 Ω |
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| OK | |
| 3.CHECK RESISTANCE OF COMMUNICATION LINE |

Disconnect the O3 and Q2 ECU connectors.
Disconnect the S5 switch connector.
Measure the resistance of the wire harness side connectors.
| Tester Connection | Specified Condition |
| O3-8 (MPX1) - Q2-8 (MPX1) | Below 1 Ω |
| O3-9 (MPX2) - S5-8 (MPX2) | Below 1 Ω |
| Result | Proceed to |
| Both are OK | A |
| One is OK | B |
| Both are NG | C |
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| A | ||
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