DTC B1242 Wireless Door Lock Tuner Circuit Malfunction |
| DTC No. | DTC Detection Condition | Trouble Area |
| B1242 | In diagnostic mode, applicable RDA signal cannot be received within 1 second of PRG signal being output from main body ECU. |
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| 1.CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - DOOR CONTROL RECEIVER) |
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Disconnect the D42 main body ECU connector.
Disconnect the G31 door control receiver connector.
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
| D42-26 (RDA) - G31-2 (RDA) | Always | Below 1 Ω |
| D42-26 (RDA) or G31-2 (RDA) - Body ground | Always | 10 kΩ or higher |
| D42-25 (PRG) - G31-3 (PRG) | Always | Below 1 Ω |
| D42-25 (PRG) or G31-3 (PRG) - Body ground | Always | 10 kΩ or higher |
| *1 | Front view of wire harness connector (to Door Control Receiver) |
| *2 | Front view of wire harness connector (to Main Body ECU) |
Reconnect the main body ECU connector.
Reconnect the door control receiver connector.
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| OK | |
| 2.INSPECT DOOR CONTROL RECEIVER (POWER SOURCE, GROUND) |
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Disconnect the G31 door control receiver connector.
Measure the voltage and resistance according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
| G31-5 (+B) - Body ground | Always | 11 to 14 V |
| Tester Connection | Condition | Specified Condition |
| G31-1 (GND) - Body ground | Always | Below 1 Ω |
| *1 | Front view of wire harness connector (to Door Control Receiver) |
Reconnect the door control receiver connector.
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| OK | |
| 3.REPLACE DOOR CONTROL RECEIVER |
Temporarily replace the door control receiver with a new or normally functioning one (Click here).
| NEXT | |
| 4.REGISTER RECOGNITION CODE |
Perform the Registration procedures (Click here).
| NEXT | |
| 5.CLEAR DTC |
Clear the DTC (Click here).
| NEXT | |
| 6.CHECK FOR DTC |
Check for DTCs (Click here).
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| OK | ||
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