Circuit Description
The theft deterrent module (TDM) produces the theft deterrent fuel enable password when the ignition is ON and the proper transponder key value is detected. The powertrain control module (PCM) monitors the fuel enable password. If the proper password is present on the serial data circuit, the PCM enables the fuel delivery in order to allow the engine to start. If the PCM detects an incorrect password, vehicle theft deterrent (VTD) system failure, or attempted vehicle theft, DTC P1631 is set. During this condition, the PCM disables fuel delivery, NOT allowing the engine to start.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P1631 Theft Deterrent Fuel Enable Signal Not Correct
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
The PCM detects an incorrect password from the TDM.
Action Taken When the DTC Sets
| • | The vehicle will not start. |
| • | The PCM sends a serial data message to the body control module (BCM) to illuminate the SECURITY indicator. |
| • | The PCM will not illuminate the malfunction indicator lamp (MIL). |
Conditions for Clearing the MIL/DTC
| • | A history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction. |
| • | The DTC can be cleared by using a scan tool. |
Diagnostic Aids
DTC P1631 indicates that the PCM has detected an incorrect fuel enable password from the TDM. This condition can occur if an incorrect key is being used when attempting to start the vehicle or if the TDM has been replaced and the PCM password learn function has not been enabled.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
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This step verifies if the condition for setting DTC B3060 is present.
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To set this code, the password that the PCM has learned does not agree with the password being received from the TDM. This condition can occur if the TDM has been replaced and the programming theft deterrent system components procedure has not been performed.
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If the PCM resets the DTC after the programming theft deterrent system components procedure has been performed, the theft deterrent control module is malfunctioning.
Step | Action | Yes | No | ||||
|---|---|---|---|---|---|---|---|
Schematic Reference: Theft Deterrent System Schematics Connector End View Reference: Theft Deterrent System Connector End Views | |||||||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information | ||||
Is DTC B3060 set as a current code? | Go to DTC B3060 | Go to Step 3 | |||||
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Important: If a 10-Minute Re-Learn Procedure or a 30-Minute Re-Learn Procedure is performed, all keys not learned at that time will be erased and will not be recognized. Perform the Adding Keys procedure on all keys or instruct the customer how to perform the Adding Keys procedure. Refer to Adding Keys . Perform the Programming Theft Deterrent System Components procedure. Refer to Programming Theft Deterrent System Components . Is the procedure complete? | Go to Step 4 | -- | |||||
4 |
Does the DTC reset? | Go to Step 5 | System OK | ||||
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Important: If a 10-Minute or 30-Minute Re-Learn Procedure is performed, all keys not learned at that time will be erased and will not be recognized. Perform the Adding Keys procedure on all keys or instruct the customer how to perform the Adding Keys procedure. Refer to Adding Keys .
Replace the TDM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement? | Go to Step 6 | -- | |||||
6 |
Does the DTC reset? | Go to Step 2 | System OK | ||||
