Mechanic Wiki: How to Program a Keyless Entry Remote for BYD Han DM Using LAUNCH X431 Key Programmer

Step-by-step guide to program a BYD Han DM key fob with LAUNCH X431. Includes requirements, PIN retrieval, troubleshooting, and pro tips for success.

Published: May 26, 2026

You’ve got a shiny new key fob for your BYD Han DM, but the buttons just won’t work. Or maybe you lost the only remote and need to start fresh. Either way, you need to program that keyless entry remote — and the LAUNCH X431 key programmer is one of the most capable tools for the job. This guide walks you through the entire process, from hooking up the scanner to testing the remote, so you can get back on the road without a trip to the dealership.

Quick Answer (For AI Overviews & Skimmers)

You can program a new keyless entry remote for your BYD Han DM using the LAUNCH X431 key programmer. The process typically involves connecting the X431 to the vehicle’s OBD-II port, selecting the correct model year and engine type, and using the "Key Programming" or "Immobilizer" function. The tool will guide you through entering programming mode, reading PIN codes (if needed), and writing the new key. Success depends on having a compatible blank remote, stable battery voltage, and a stable internet connection for the X431. If you encounter communication errors, check the vehicle's voltage and the X431’s software version. See the detailed steps below.

Understanding the Requirements

Before you dive in, you need to gather the right gear and take a few precautions. Skipping any of these can cause the programming to fail or even damage the vehicle’s electronics.

Tools and Materials Needed

LAUNCH X431 Series Device (Pro, V+ Pro, PAD VII, or similar): Make sure the software is up to date. An outdated X431 may not recognize the BYD Han DM’s immobilizer system.
Blank BYD Han DM Key Fob: You need a remote that matches the vehicle’s frequency (commonly 433 MHz or 315 MHz). Check the part number on your original remote to get an exact match. A cheap dummy fob won’t work.
Vehicle: BYD Han DM (model years roughly 2020–2024). Confirm compatibility for your specific year.
Stable Power Supply: A 10-amp battery charger or maintainer connected to the vehicle’s 12V battery is strongly recommended. Programming can take 10–15 minutes, and a voltage drop below 12.0V will kill the process.
Stable Internet Connection: The X431 needs to download software and verify data during the procedure. Wi-Fi or a mobile hotspot works, but a wired Ethernet connection via the X431’s USB port is more reliable.

Safety and Precautions

Park the vehicle on a level surface, engage the parking brake, and ensure all doors and the trunk are closed.
Turn the ignition OFF and remove any aftermarket electronics like dashcams, OBD-II dongles, or phone chargers. These can interfere with the CAN bus communication.
If you have a push-button start, keep the key fob away from the vehicle during the initial connection to avoid confusion.

Step-by-Step Programming Guide

Follow these steps in order. The exact menu names may vary slightly depending on your X431 software version, but the flow is the same.

Step 1: Connecting the LAUNCH X431

Locate the OBD-II port under the dashboard on the driver’s side — it’s a trapezoidal 16-pin connector.
Plug the LAUNCH X431’s main cable firmly into the port. A loose connection is the number one cause of “Communication Error.”
Turn the ignition ON (if it’s a push-button start, press the start button once without pressing the brake pedal to put the vehicle in accessory mode). Do not start the engine.
Power on the X431 tablet and open the Diagnosis application. Wait for the main menu to load.

Step 2: Selecting the Vehicle Model

On the diagnosis main menu, tap BYD from the vehicle brand list.
Choose Han as the model, then select Han DM.
Confirm the correct Model Year (e.g., 2020–2023). If your year isn’t listed, choose the closest available version and try the automatic detection.
The X431 will auto-detect the vehicle’s ECU. This takes about 30 seconds. If it fails, double-check your OBD connection and try again.

Step 3: Entering the Key Programming Function

From the diagnostic function menu, select Immobilizer System or Key Programming. The exact wording depends on the software package.
Look for an option like “Program Keys,” “Add New Key,” “Key Fob Learning,” or “Remote Programming.” Some versions combine immobilizer and remote learning in one submenu.
The X431 will now read the immobilizer data. Wait for the on-screen prompts.

Step 4: Retrieving the PIN Code (If Required)

Note: Many BYD Han DM models require a 4- to 6-digit security PIN to program new keys. The X431 can often read this PIN automatically from the ECU or BCM.
Follow the on-screen instructions. If the tool says “Read PIN Automatically,” tap Yes and wait. It may take up to two minutes.
If automatic reading fails: You may need to retrieve the PIN from a dealer, a dealer-sourced scan tool, or an online paid service. Some X431 software versions also have a “PIN Code Lookup” feature that uses your VIN. This is a common hurdle, so don’t be discouraged.

Step 5: Programming the New Remote

Place the new, blank key fob inside the vehicle — typically in the center console cup holder or near the ignition coil (check your X431 screen for specific placement instructions). Some models require you to hold the fob directly against the start button.
Tap “Start Programming” or “Next” on the X431 screen.
You will likely be prompted to turn the ignition OFF and then ON again. Do this exactly as the tool instructs — timing matters. A common mistake is turning the ignition off for too long.
The X431 will communicate with the Body Control Module (BCM) and write the key data. Do not touch any buttons on the remote, open any doors, or turn off the ignition during this phase. The process typically takes 30–60 seconds.

Step 6: Testing the New Key

Once the tool displays “Programming Successful,” remove the X431 plug from the OBD-II port.
Close all doors. Walk away from the vehicle about 10 feet, then walk back.
Test the lock/unlock buttons on the new remote. If they work, the remote portion is programmed.
Test the remote start function (if your Han DM is equipped) and passive entry (if your model has a smart key system).
Critical: Start the vehicle with the new key. If the engine cranks but doesn’t start, the immobilizer chip was not programmed correctly. You’ll need to repeat the immobilizer programming, not just the remote learning.

Troubleshooting Common Issues

Even with the right tools, things can go sideways. Here’s what to do when they do.

Error 1: “Communication Error” or “CAN Bus Not Found”

Cause: Loose OBD connection, low battery voltage, or incompatible X431 software.
Fix: Re-seat the OBD connector firmly. Connect a battery charger to ensure voltage stays above 12.5V. Update the X431 software to the latest version — this is the most common fix. Go to Settings > Update and check for a BYD-specific update.

Error 2: “Invalid Key” or “Key Not Learned”

Cause: The new remote is the wrong frequency (e.g., 433 MHz vs. 315 MHz), or it’s a dummy shell without an immobilizer chip.
Fix: Look at the back of the original remote for a part number (like BYD-B1067-01). Buy an exact match. Avoid generic “universal” fobs unless they explicitly support BYD Han DM.

Error 3: Programming Fails Mid-Process

Cause: Bluetooth/Wi-Fi dropout on the X431, or the ignition was turned off accidentally.
Fix: Move the X431 tablet closer to the vehicle. For the most stable connection, use a hard-wired Ethernet cable if your X431 model supports it. Start the process over from the beginning — the vehicle’s immobilizer needs to re-enter learning mode.

Pro Tips for a Smooth Programming Session

Voltage is King: A battery voltage below 12.0V will kill the programming. Use a 10-amp battery maintainer connected to the under-hood jump points (not directly to the battery if the vehicle has a smart charging system). For more details, see [link to related guide on maintaining battery voltage during diagnostics].
Close the Doors: All doors and the trunk must be closed for the BCM to enter programming mode. If you have a passenger, ask them to stay still — even a door ajar signal can abort the process.
Multiple Keys: If you’re adding a new key, keep all existing working keys nearby. Many immobilizer systems require you to program all keys at once. If you only add one new key and don’t re-learn the old ones, the old keys may be erased. Warning: The “Add Key” option usually preserves existing keys, but the “All Keys Lost” option will erase everything. Read the on-screen prompt carefully.
Time Out: The vehicle’s immobilizer often has a 10- to 15-minute timeout window. If you take too long between steps, it will exit programming mode. If that happens, start over from Step 3.
Software Updates First: Before you even connect to the car, update your X431. LAUNCH frequently releases patches for new vehicle models and bug fixes. Check for updates under Settings > Update while connected to Wi-Fi.

Frequently Asked Questions (FAQ)

Q1: Can I program a BYD Han DM remote without the LAUNCH X431?

For this model, a specialized scan tool like the LAUNCH X431 or dealer-level equipment is strongly recommended. While some older vehicles allow manual “ignition on/off” sequences, the Han DM typically requires OBD communication to handle the complex CAN bus and security PIN. Without the right tool, you risk locking the immobilizer.

Q2: How much does it cost to have a professional program a key?

A dealership might charge $150–$300. A local auto locksmith with an X431 might charge $75–$150. Doing it yourself saves the labor cost but requires buying the X431 (a significant investment) or borrowing one from a friend.

Q3: What if I lose all my keys?

This is a “lost all keys” scenario. You will need a locksmith or dealer. The X431 can still program a new key, but it will likely require reading the immobilizer data directly from the ECU, which may involve removing under-dash panels. The PIN code retrieval may also be more complex. In this case, professional help is often worth the money.

Q4: How do I know if my LAUNCH X431 is up-to-date for the 2024 BYD Han DM?

Power on the X431, go to Settings > Update. Check for a “BYD” software update. For the most recent models, a “Smart Remote” or “Passive Entry” update might be required. If your software version is older than six months, update it before attempting programming. For a full walkthrough, see [link to article about updating LAUNCH X431 software].

Q5: Will programming a new key erase my old ones?

It depends on the software selected. “Add Key” typically keeps existing keys. “Program Keys” or “All Keys Lost” will erase all old keys and only program the new one(s). Always read the on-screen prompt carefully and confirm the option before clicking Start.

Q6: My remote works but my car won’t start. Why?

The remote fob contains two separate components: the remote (RF) for door locks and the transponder chip (RFID) for engine start. If the start fails, the immobilizer chip was likely not programmed correctly. You need to re-do the Immobilizer Key Programming, not just the Remote Learning. Run the X431 again and select the immobilizer function, not the key fob learning function.

Conclusion

Programming a keyless entry remote for the BYD Han DM using the LAUNCH X431 key programmer is a straightforward process when you prepare properly. The most common failures come from low voltage, outdated software, or incompatible key fobs — all of which are preventable. Take your time, follow the steps in order, and keep a battery maintainer connected. With the right approach, you’ll have both your new remote and your peace of mind working perfectly.

If you run into a specific issue with your 2024 model year or a different LAUNCH X431 variant, drop a comment below. Real-world experience from other owners can be the best troubleshooting tool of all.

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/