DTC B1204 Driver Side Seat Switch ECU Communication Stop |
| DTC No. | DTC Detection Condition | Trouble Area |
| B1204 | Integration control and panel assembly communication stops |
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| 1.CHECK WIRE HARNESS (INTEGRATION CONTROL AND PANEL ASSEMBLY - BATTERY AND BODY GROUND) |
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Disconnect L12 ECU connector.
Measure the voltage and resistance of the wire harness side connector.
| Tester Connection | Specified Condition |
| L12-6 (+B) - Body ground | 10 to 14 V |
| Tester Connection | Specified Condition |
| L12-2 (GND) - Body ground | Below 1 Ω |
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| OK | |
| 2.CHECK WIRE HARNESS (INTEGRATION CONTROL AND PANEL ASSEMBLY - GATEWAY ECU) |

Disconnect the L12 and L66 ECU connectors.
Measure the resistance of the wire harness side connectors.
| Tester Connection | Specified Condition |
| L12-5 (MPX1) - L66-4 (MPI1) | Below 1 Ω |
| L12-5 (MPX1) - Body ground | 10 kΩ or higher |
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| OK | |
| 3.CHECK WIRE HARNESS (INTEGRATION CONTROL AND PANEL ASSEMBLY - A/C AMPLIFIER) |

Disconnect the L12 ECU connector.
Disconnect the L52 A/C amplifier connector.
Measure the resistance of the wire harness side connectors.
| Tester Connection | Specified Condition |
| L12-8 (MPX2) - L52-31 (MPX-) | Below 1 Ω |
| L12-8 (MPX2) - Body ground | 10 kΩ or higher |
| Result | Proceed to |
| Both are OK | A |
| One is OK | B |
| Both are NG | C |
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| A | ||
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