P1631 2018 GMC Sierra Code - Theft Deterrent Start Enable Signal Not Correct
Quick Answer
The P1631 diagnostic trouble code (DTC) for a 2018 GMC Sierra indicates that the theft deterrent start enable signal is not correct. Common causes include Faulty key or key fob, Malfunctioning receiver in the vehicle, Wiring issues between the key/ key fob and receiver. 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 2018 GMC Sierra indicates Theft Deterrent Start Enable Signal Not Correct.
- Common causes
- Common causes include Faulty key or key fob, Malfunctioning receiver in the vehicle, Wiring issues between the key/ key fob and receiver.
- 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.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.
Code P1631 2018 GMC Sierra Description
The P1631 diagnostic trouble code (DTC) for a 2018 GMC Sierra indicates that the theft deterrent start enable signal is not correct. This code is related to the vehicle's security system, specifically the immobilizer system that prevents the engine from starting without the correct key or key fob. When this code is triggered, it means that the signal sent by the theft deterrent system to enable the engine start is not being recognized or is incorrect.
Common Causes of P1631 2018 GMC Sierra
- Faulty key or key fob.
- Malfunctioning receiver in the vehicle.
- Wiring issues between the key/ key fob and receiver.
- Low battery in the key or key fob.
- Faulty immobilizer module.
Symptoms of P1631 2018 GMC Sierra
- Engine cranks but does not start.
- Security light on the dashboard stays illuminated.
- Inability to start the engine with the correct key or key fob.
- Vehicle goes into anti-theft mode and does not respond to key inputs.
How to Fix P1631 2018 GMC Sierra
- Check the key or key fob for any visible damage or low battery. Replace the battery if necessary.
- Inspect the receiver in the vehicle for any signs of damage or malfunction. Replace if needed.
- Check the wiring connecting the key/ key fob to the receiver for any breaks or shorts. Repair or replace as necessary.
- If all components check out, perform a relearn procedure for the theft deterrent system to re-sync the key/ key fob with the receiver.
- If the issue persists, consider replacing the immobilizer module.
Cost to Fix P1631 2018 GMC Sierra
The typical repair costs for addressing a P1631 code on a 2018 GMC Sierra can vary depending on the specific cause of the issue. In general, replacing a key fob battery can cost around $5-$20, while a new key fob can range from $50-$200. Repairing or replacing the receiver in the vehicle may cost between $100-$300, and addressing wiring issues can range from $50-$200. If the immobilizer module needs to be replaced, this can cost anywhere from $200-$500. It's important to note that these are rough estimates, and actual costs may vary based on factors such as location, labor rates, and parts availability. It's recommended to consult with a qualified mechanic or dealership for a more accurate cost estimate.
Tech Notes for P1631 2018 GMC Sierra
-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.
Need more information about the P1631 2018 GMC Sierra code?
Need more information on how to fix the P1631 2018 GMC Sierra code? Get Access to Factory Service Manuals
Need Help with the Code?
Get the P1631 2018 GMC Sierra code diagnosed by a professional: Find a repair shop in your area
Frequently Asked Questions about P1631 2018 GMC Sierra Code
1. What are the common symptoms of OBDII code P1631 in a 2018 GMC Sierra?
The common symptoms of OBDII code P1631 in a 2018 GMC Sierra include the vehicle not starting, the security light flashing, and a message indicating "Theft Deterrent System Problem" on the dashboard.
2. What does the OBDII code P1631 indicate in a 2018 GMC Sierra?
OBDII code P1631 in a 2018 GMC Sierra indicates a problem with the Theft Deterrent Start Enable Signal not being correct, which can prevent the vehicle from starting.
3. What are the possible causes of OBDII code P1631 in a 2018 GMC Sierra?
Possible causes of OBDII code P1631 in a 2018 GMC Sierra include a faulty ignition key, issues with the ignition switch, problems with the immobilizer system, or a malfunction in the body control module.
4. How can I diagnose the OBDII code P1631 in my 2018 GMC Sierra?
Diagnosing OBDII code P1631 in a 2018 GMC Sierra may involve checking for any loose connections in the ignition system, testing the ignition key for proper functioning, and using a diagnostic scanner to retrieve specific error codes related to the theft deterrent system.
5. Can I drive my 2018 GMC Sierra with OBDII code P1631?
It is not recommended to drive your 2018 GMC Sierra with OBDII code P1631, as this code indicates a security issue that may prevent the vehicle from starting or lead to unexpected engine shutdowns.
6. How can I repair OBDII code P1631 in my 2018 GMC Sierra?
Repairing OBDII code P1631 in a 2018 GMC Sierra may involve reprogramming the ignition key, replacing a faulty ignition switch, repairing the immobilizer system, or resetting the body control module to resolve the issue.
7. Is it safe to reset the OBDII code P1631 in a 2018 GMC Sierra using a diagnostic scanner?
Resetting OBDII code P1631 in a 2018 GMC Sierra using a diagnostic scanner may clear the error code temporarily, but it is crucial to address the root cause of the issue to prevent the code from reoccurring and ensure the vehicle's security system is functioning correctly.
8. Can a DIY enthusiast fix OBDII code P1631 in a 2018 GMC Sierra?
While some basic troubleshooting steps can be performed by a DIY enthusiast, diagnosing and repairing OBDII code P1631 in a 2018 GMC Sierra may require specialized tools and expertise, so it is advisable to consult a professional mechanic for a thorough inspection and repair.
9. How much does it typically cost to repair OBDII code P1631 in a 2018 GMC Sierra?
The cost of repairing OBDII code P1631 in a 2018 GMC Sierra can vary depending on the specific cause of the issue, parts needed for replacement, and labor charges. It is recommended to obtain quotes from reputable repair shops or dealerships for an accurate estimate.
10. Will OBDII code P1631 in a 2018 GMC Sierra affect the vehicle's performance?
OBDII code P1631 in a 2018 GMC Sierra may not directly impact the vehicle's performance once the issue is resolved. However, unresolved security system problems can lead to starting issues or potential engine immobilization, affecting the overall functionality of the vehicle.
Discuss the causes and fixes for P1631 2018 GMC Sierra OBDII Code
Code P1631 2018 GMC Sierra comments
No comments found for this page.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.