GAC Vehicle Programming 

How to Add a Spare Smart Key to a GAC Trumpchi GS5 (2018–2021) Using LAUNCH X431

• June 17, 2026
Step-by-step guide to program a spare smart key for a 2018–2021 GAC Trumpchi GS5 with LAUNCH X431. Includes requirements, troubleshooting, and FAQs.

Quick Answer: Programming a Spare Smart Key to a GAC Trumpchi GS5 (2018–2021) with LAUNCH X431

Yes, you can add a spare smart key yourself using an LAUNCH X431 scan tool. The process involves connecting the tool, entering the vehicle’s immobilizer system, and following on-screen prompts to program the new key. All existing working keys must be present during the procedure. Expect the job to take 10–20 minutes. If you lack a working key or the tool fails to communicate, consult a professional locksmith.

Introduction

Losing or damaging the only smart key for your 2018–2021 GAC Trumpchi GS5 can be stressful. While dealership programming is an option, it’s often expensive and time-consuming. By using an LAUNCH X431 diagnostic scanner (such as the X431 Pro, V, or Pad series), you can add a spare smart key to your GAC Trumpchi GS5 yourself, saving money and gaining control over your vehicle’s access.

This guide walks you through the exact steps, required tools, common pitfalls, and answers to frequently asked questions. Whether you’re a DIY enthusiast or a small workshop owner, you’ll find everything you need to complete the job confidently.

What You’ll Need

Before you begin, gather the following:

  • LAUNCH X431 scan tool – with the latest software update and an active subscription that includes GAC or Trumpchi modules (Chinese vehicle package or Asia package)
  • Blank smart key – must be compatible with the GS5 (2018–2021). Check the part number or FCC ID on your original key to match frequencies
  • All existing working smart keys – usually required to authenticate the programming session
  • Stable internet connection – the scanner may need to download vehicle-specific software or perform PIN retrieval
  • Vehicle with good battery voltage (12V+) – low battery can interrupt communication

Pro tip: Write down the security code if you find it on a card in the glove box manual. It saves a few minutes during the process.

Step-by-Step: Programming a Spare Smart Key with LAUNCH X431

1. Prepare the Vehicle and Tool

  1. Turn the ignition OFF and ensure all doors are closed.
  2. Connect the LAUNCH X431 to the OBD-II port (located under the driver’s side dashboard).
  3. Power on the scan tool and select Diagnostics.
  4. Choose GAC or Trumpchi (depending on your software version) → GS5 → select the model year range (2018–2021).

Expected outcome: The tool loads the vehicle system list and displays available control units.

2. Enter the Immobilizer System

  1. From the system list, navigate to Immobilizer or Security/Anti-Theft.
  2. Select Key Programming or Add Key.
  3. If the tool prompts for a security code (PIN), enter it now. The code is often found:
    • On a plastic card stored with the owner’s manual.
    • Printed on the immobilizer module under the dashboard.
    • Retrieved via the X431’s PIN Retrieval function (requires internet and takes about 5 minutes).

If you don’t have the code and the retrieval fails, you may need to contact a dealer with your VIN.

3. Start Programming

Follow the on-screen instructions carefully. A typical sequence looks like this:

  • Step A: Insert the first existing working key into the ignition (or hold it near the start button for smart keys). Turn ignition ON (or press the start button once). The tool will recognize the key.
  • Step B: Remove the first key and repeat with any additional working keys you want to keep functional.
  • Step C: Finally, insert the new blank smart key and turn ignition ON. The tool will display “Programming Successful” within a few seconds.

What to watch for: Some GS5 variants require you to press the lock/unlock button on each key during the sequence. The on-screen prompts will guide you.

4. Verify the New Key

  1. Disconnect the LAUNCH X431.
  2. Test all keys (including the new one):
    • Lock and unlock the doors.
    • Start the engine.
    • Check remote functions (trunk release, panic alarm).
  3. If the new key doesn’t work, repeat the entire process. Ensure the blank key is fresh and compatible.

Troubleshooting Common Issues

Even with the right tool, things can go wrong. Here’s how to handle the most common problems:

Issue Likely Cause Solution
Tool doesn’t find GS5 model Outdated software or missing GAC module Update the X431 via Wi‑Fi; verify your subscription includes Chinese vehicles
“Communication Error” appears Loose OBD connection or low battery Reconnect the scanner, restart the vehicle, or charge the battery
Security code unknown Code not documented or not in vehicle Use the X431’s PIN retrieval; if that fails, contact a dealer with VIN
New key not recognized Wrong frequency or previously programmed Check key part number (433 MHz for 2018–2019; 433 or 868 MHz for 2020–2021); use a new blank
All keys lost No working key to authenticate Requires dealer-level tools or a professional locksmith

Essential Context & Related Topics

Why Add a Spare Key?

  • Avoid lockout emergencies.
  • Share access with family members.
  • Prevent costly full-system replacement if the only key is lost or damaged.

Key Compatibility by Year

  • 2018–2019 GS5: Uses 433 MHz frequency.
  • 2020–2021 GS5: May use 433 MHz or 868 MHz depending on the region. Always cross‑check the FCC ID on your original key.

Programming vs. Cloning

  • Programming (this guide): The LAUNCH X431 adds the new key’s unique ID to the vehicle’s immobilizer list. Existing keys remain functional.
  • Cloning: Copies the exact RFID data from a working key. Not recommended for smart keys because it duplicates the same ID, which can cause conflicts.

When to Seek Professional Help

  • You have zero working keys – the X431 procedure requires at least one valid key.
  • The tool repeatedly fails PIN retrieval – the immobilizer may be locked.
  • The vehicle has an aftermarket alarm system that interferes with communication.

Frequently Asked Questions

Q: Can I program a key without the original?
No, the LAUNCH X431 procedure requires at least one working key to authenticate. For zero-key situations, use a dealer or an advanced locksmith with a key generation tool.

Q: Does the LAUNCH X431 need a specific subscription for GAC?
Yes, you need the GAC/Trumpchi path or a Chinese vehicle package in your X431 subscription. Some versions include it under the “Asia” or “Domestic” module. Check before starting.

Q: How many keys can the GS5 store?
Typically up to 8 keys. You can add more by repeating the programming sequence. If you reach the limit, you’ll need to erase unused keys first.

Q: The tool says “Key Already Exists” – what now?
This means the blank key was previously programmed to another vehicle. It must be new and unused. Return it and buy a fresh blank.

Q: Can I use a key from another GAC model (e.g., GA4)?
No – the GS5 uses a different transponder and remote frequency. Use only a key labeled for the 2018–2021 GS5.

Q: Will this process erase my existing keys?
No, the “Add Key” function only adds a new key. However, if you accidentally select “Erase All Keys,” it will delete all programmed keys – so choose carefully.

Q: My X431 is up to date but the immobilizer menu is missing.
Try selecting System Tests → Body Control Module → Keyless Entry instead. Some GS5 variants place key programming under BCM rather than a dedicated immobilizer menu.

Q: How long does the new key battery last?
Approximately 2–3 years. Replace with a CR2032 battery when the range decreases.

Q: Is it legal to program my own key?
Yes, for personal use. The LAUNCH X431 is a legitimate diagnostic tool. Reselling programming services may require licensing depending on your country.

Final Tips

  • Keep a printed copy of the security code with your vehicle documents. It’s easy to forget.
  • Test all keys immediately after programming – if one fails, reprogram all keys together.
  • For advanced features like hands-free passive entry, perform a manual synchronization step after programming: press the lock button on the new key five times near the vehicle.
  • If you encounter persistent issues, refer to the LAUNCH X431 manual or contact their support. For more guidance on diagnostic tool operations, check out our article on [common immobilizer programming mistakes](link to related guide on similar topic).

Published: June 16, 2026

About the Author: Erwin Salarda is an Automotive Service Equipment Technician based in the Philippines, specializing in computerized automotive diagnostic equipment such as OBD scanners and wheel alignment systems. Since 2012, he has been actively providing technical support, equipment installation, troubleshooting, after-sales service, and hands-on training for automotive service equipment used by workshops and automotive professionals.

He has received specialized training from international suppliers and manufacturers, including Launch X431 in Shenzhen, China, Lawrence Engineering Company in Guangzhou, China, and 3Excel Wheel Alignment Company in Shenzhen, China. Through these trainings, he developed advanced expertise in automotive diagnostics, calibration, wheel alignment systems, and computerized automotive service technologies.

Erwin Salarda provides professional after-sales support and technical training for automotive diagnostic and wheel alignment equipment, helping clients maximize the performance and proper use of their tools and systems. His experience covers equipment setup, software updates, calibration procedures, troubleshooting, and operational guidance for automotive workshops and service centers.

With more than a decade of experience in the automotive equipment industry, Erwin Salarda continues to support automotive businesses by delivering reliable technical expertise and practical training solutions.

For inquiries and equipment purchases, please visit https://carlifterph.com/

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