P1631 GMC Code - Theft Deterrent Start Enable Signal Not Correct
Quick Answer
The P1631 GMC code indicates that the Theft Deterrent System (TDS) Start Enable signal is not correct. Common causes include Faulty ignition lock cylinder, Malfunctioning ignition switch, Issues with the Body Control Module (BCM). Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P1631 GMC indicates Theft Deterrent Start Enable Signal Not Correct.
- Common causes
- Common causes include Faulty ignition lock cylinder, Malfunctioning ignition switch, Issues with the Body Control Module (BCM).
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
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Code P1631 GMC Description
The P1631 GMC code indicates that the Theft Deterrent System (TDS) Start Enable signal is not correct. This system is designed to prevent unauthorized individuals from starting the vehicle by disabling the ignition. When this code is triggered, it means that the vehicle's computer has detected an issue with the signal that enables the vehicle to start, potentially due to a malfunction in the TDS components or wiring.
Common Causes of P1631 GMC
- Faulty ignition lock cylinder
- Malfunctioning ignition switch
- Issues with the Body Control Module (BCM)
- Wiring or connection problems in the TDS circuit
- Key fob battery depletion or malfunction
Symptoms of P1631 GMC
- Intermittent starting issues
- Inability to start the vehicle
- Security light flashing on the dashboard
- Engine stalling shortly after starting
- Loss of power while driving
How to Fix P1631 GMC
- Diagnose the specific cause of the issue using a diagnostic scanner to retrieve the fault codes and pinpoint the source of the problem.
- Inspect the ignition lock cylinder and ignition switch for any signs of wear or damage. Replace these components if necessary.
- Check the wiring and connections in the TDS circuit for any loose connections or damaged wires. Repair or replace any faulty components.
- Test the key fob battery and replace it if needed. Ensure that the key fob is programmed correctly to communicate with the vehicle's security system.
- Clear the fault codes from the vehicle's computer and perform a test start to verify that the issue has been resolved.
Cost to Fix P1631 GMC
The typical repair costs for addressing a P1631 GMC code can vary depending on the specific cause of the issue and the labor rates at the auto repair shop. In general, the cost of replacing the ignition lock cylinder or ignition switch can range from $150 to $300, while addressing wiring or connection issues may cost between $100 and $200. Key fob battery replacement is relatively inexpensive, typically costing around $10 to $20. Additionally, labor costs can range from $80 to $150 per hour, with the total repair cost varying based on the extent of the repairs needed. It is recommended to consult with a qualified mechanic to get an accurate estimate for resolving this issue.
Tech Notes for P1631 GMC
-Insert the key, attempt to start the vehicle, and leave the key in the ON position.
In some vehicles, the Battery and Security light will blink for several seconds, and then shut off. Then the Security light will then remain ON. Leave the ignition ON until the Security light goes OFF. This will take more than 5 mins.
-When the Security light goes OFF, turn the ignition to the OFF position.
-Leave ignition OFF for 20 Seconds.
-Attempt to start the vehicle again and leave the key in the ON position.
-In some vehicles, the Battery and Security light will blink for several seconds, and then shut off. Then the Security light will then remain ON. Leave the ignition ON until the Security light goes OFF. This will take more than 5 mins.
-Turn the ignition to the OFF position for 20 Seconds.
-Attempt to start the vehicle again and leave the key in the ON position.
-In some vehicles, the Battery and Security light will blink for several seconds, and then shut off. Then the Security light will then remain ON. Leave the ignition ON until the Security light goes OFF. This will take more than 5 mins.
-Once this entire procedure has been completed (three times) your vehicle will start on the fourth attempt.
Note: Some vehicles perform the relearn in a different sequence. You may notice your security light, battery light, and abs light will alternate. Once the security light is left out of the sequence that is considered one step. Repeat the procedure two more times and on the fourth time, your vehicle will start.
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Information for Specific GMC Models
- P1631 2014 GMC Sierra — Theft Deterrent Start Enable Signal Not Correct
- P1631 2015 GMC Sierra — Theft Deterrent Start Enable Signal Not Correct
- P1631 2016 GMC Sierra — Theft Deterrent Start Enable Signal Not Correct
- P1631 2017 GMC Sierra — Theft Deterrent Start Enable Signal Not Correct
- P1631 2018 GMC Sierra — Theft Deterrent Start Enable Signal Not Correct
Frequently Asked Questions about P1631 GMC Code
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