How to Program Bentley Bentayga All Keys Lost via LAUNCH X431

Quick Answer

Programming a Bentley Bentayga after an "All Keys Lost" situation using a LAUNCH X431 requires specialized immobilizer software and a valid 5-digit security code. You must connect the X431, select the IMMO Elite function, enter the PIN, erase all existing keys, then program two new blank Bentley OEM transponders. The entire process takes 30–60 minutes and demands a stable battery voltage above 12.5V. If successful, both new keys will start the engine and operate remote functions.

Understanding the Challenge: Bentley Bentayga All Keys Lost

Losing every key to a Bentley Bentayga is not a simple inconvenience — it's a high-stakes immobilizer crisis. Unlike programming a single additional key (which simply adds a new transponder without erasing the others), an "All Keys Lost" procedure requires a full reset of the Bentley’s Body Control Module (BCM) memory. This wipes every stored key ID, then enrolls fresh ones from scratch.

Why is this so risky? Because the Bentayga’s immobilizer system is tightly integrated with the KESSY (Keyless Entry, Start, and Exit) module, the engine ECU, and the steering column lock. A single misstep — like entering the wrong PIN three times or interrupting the erase step — can permanently lock the ECU, forcing a costly dealer visit. According to experienced automotive locksmiths, the recovery cost for a locked Bentley ECU can exceed $2,000, plus towing.

The key difference between adding a key and recovering from an all-keys-lost scenario lies in the erase command. When you program a new key with at least one working key present, the BCM simply adds the new transponder to its memory list. But when no keys exist, the BCM must first clear its entire key table. That erase step is where most beginners get into trouble.

Prerequisites Before You Start

Required Hardware

Required Software & Data

• Latest X431 firmware and IMMO Elite software — check for updates under the IMMO menu before starting. If you skip updates, the tool may not recognize the Bentayga’s immo system.
• Vehicle 5-digit security code (PIN) — obtain this from a Bentley dealer using your VIN, or use X431’s online PIN retrieval service (available in some regions for a per-VIN fee).
• Battery voltage above 12.5V — connect a maintainer to the battery posts, not the OBD port, for the most stable supply.
• Stable internet connection — needed for cloud-based PIN requests and software verification.

Important: Do not attempt this procedure on a low battery. A voltage drop during the erase step can corrupt the BCM’s flash memory, requiring a full module replacement.

Step-by-Step: Programming Bentley Bentayga All Keys Lost

Step 1: Prepare the Vehicle and X431

1. Connect a battery maintainer to the Bentley’s battery terminals under the hood (not the OBD port).
2. Turn the ignition OFF and close all doors.
3. Plug the X431 into the OBD-II port (located beneath the driver’s side dashboard).
4. Power on the X431 and launch the IMMO app from the main dashboard.
5. Select Bentley → Bentayga → confirm the model year range (e.g., 2016–2024).

The X431 will automatically detect the vehicle’s VIN and protocol. If it asks for a manual VIN entry, type it carefully — one wrong digit can pull the wrong immobilizer configuration.

Step 2: Read and Save Immobilizer Information

Before making any changes, always capture baseline data. Navigate to Immobilizer → Read Immobilizer Status. The tool will display:

• ECU Part Number (e.g., 4H0 907 064 BK)
• Software Version (e.g., 0125)
• VIN

Take a screenshot or photo of these values on the X431 screen. Why? If something goes wrong — like a failed erase or a power loss — a Bentley dealer will need this exact ECU part number and software version to order a replacement or recover the module. Without this record, the recovery process becomes much harder and more expensive.

Next, select "All Keys Lost" or "Erase & Program Keys." The exact wording depends on your X431 software version. If you see only "Add Key" without an erase option, you are likely running a standard IMMO license, not IMMO Elite. Stop here and upgrade.

Step 3: Enter Security Access (PIN Code)

This is the most sensitive step in the entire procedure.

• Choose "PIN/Code Retrieval" if you want the X431 to request the code online (requires payment per VIN). Enter the VIN, wait 2–5 minutes for the server response.
• Choose "Manual PIN Entry" if you already have the 5-digit code from a dealer or locksmith.

Enter the PIN slowly and verify each digit. Do not retry more than three times. After three incorrect attempts, the BCM locks the immobilizer for a timed period (typically 10–15 minutes with ignition OFF). After a lockout, further incorrect attempts can permanently freeze the module.

If your PIN is rejected on the first attempt, double-check the VIN and the PIN source. Bentley PINs are often derived from the vehicle’s specific configuration and may vary by model year. A common mistake is using a PIN from a different Bentley model (e.g., Continental GT PIN on a Bentayga).

Step 4: Erase All Existing Keys

After successful PIN verification, select "Erase All Keys." The X431 will display a warning: "This will delete all current keys. Continue?"

Select Yes. The tool then sends an erase command to the BCM. During this 30–60 second window:

• Do not touch the ignition.
• Do not open any doors.
• Do not disconnect the X431.
• Do not interrupt the battery maintainer.

The BCM clears its entire key memory table. If the process is interrupted by a power loss or a loose OBD connection, the module can become partially programmed — a state many technicians call "bricked." Once bricked, the ECU must be removed, sent to a specialist, and reprogrammed using dealer-level tools like ODIS or VCDS VAS.

After the erase completes, the X431 will display: "Key memory erased. Ready for programming."

Step 5: Program New Keys (Add Key Function)

Now you can add the new keys one by one.

1. Select "Add Key" or "Program Key" from the menu.
2. Insert the first new blank key into the ignition slot (or place it inside the key reader cup for push-button start models). Turn the key to the ON position — do not start the engine.
3. Press "Start Programming" on the X431.
4. The tool will communicate with the transponder and write the key ID to the BCM. Wait for the on-screen prompt: "Learn successful. Do you want to program another key?"
5. Select Yes, then repeat the process with the second key.
6. After both keys are programmed, turn the ignition OFF, remove the key, then re-insert the second key and turn it ON to confirm the BCM recognizes both IDs.
7. The X431 will display "Program completion".

Step 6: Program Remote (Key Fob) Functions

On some Bentayga models, the transponder and remote functions are programmed separately. If your X431 does not automatically handle remotes, follow this sub-step:

1. From the IMMO menu, select "Remote Programming" → Bentley Bentayga.
2. The tool will display the manual pairing procedure for your model year. Typically, you need to:
   • Press the Lock button on the new key three times within 10 seconds.
   • Or press Lock + Unlock simultaneously for 5 seconds.
3. Test both keys: lock/unlock doors, open the trunk, and test the panic alarm.

If the remote functions still do not respond, check the key’s battery (CR2032). A weak battery can prevent the fob from transmitting the rolling code during the pairing sequence.

Step 7: Test All Functions

Before declaring success, perform a thorough test:

• Start the engine with each new key. The engine should crank and run without any hesitation.
• Check the dashboard for warnings like "Key Not Detected" or "Immobilizer Active."
• Test keyless entry (if equipped): walk up to the door with the key in your pocket and pull the handle.
• Test push-button start: press the Start button with the key inside the vehicle.
• Test remote functions at a distance of at least 10 meters.

If any test fails, the key may not be fully programmed. Return to Step 5 and re-run the "Add Key" sequence for that specific key.

Post-Programming Verification & Troubleshooting

Common Issues and Fixes

Advanced Troubleshooting

• If programming fails mid-way: Do not turn the ignition OFF. Reboot the X431, reconnect to the vehicle, and try "Add Key" again. The BCM may still be in learn mode for up to 5 minutes.
• If the ECU is completely locked: Only dealer-level tools (ODIS, VCDS-like VAS) can unlock it. The X431 cannot bypass a permanent security lockout.
• For Bentayga Hybrid models: Additional high-voltage system safety precautions apply. Consult the X431-specific hybrid guide before starting.

Topical Depth: What Else You Need to Know

Differences by Model Year

For 2024+ Bentaygas, the X431 IMMO Elite software may not yet support the new 4D80 transponder. Always check the X431 compatibility list or contact LAUNCH support before attempting.

Alternative Tools If X431 Fails

If your X431 cannot complete the procedure, consider these alternatives:

• Autel IM508 / IM608 — often more reliable for European all-keys-lost jobs, especially for Bentley and Rolls-Royce.
• JLR SDD / VAS 5054 — genuine dealer-grade tools that can handle any immobilizer lockout.
• OBDSTAR X300M — a budget-friendly option, but success rates on Bentayga are lower, particularly for 2020+ models.

Cost Considerations

• Bentley dealer labor for key programming: $200–$500+ per key
• X431 ownership cost (tool + IMMO Elite subscription): $500–$2,500
• Blank OEM key cost: $100–$300 each
• Online PIN retrieval fee (via X431): $10–$30 per VIN (varies by region)

If you are a locksmith or independent shop, investing in the right tool pays off after just a few Bentley jobs.

Best Practices for Success

1. Always use a battery maintainer — a dead battery mid-program is catastrophic. Use one that provides at least 10 amps.
2. Never skip the PIN retrieval step — guessing the PIN or using a wrong code can lock the ECU for hours or permanently.
3. Test both keys immediately — if you leave the shop with only one working key and it fails later, the BCM will require another erase cycle.
4. Keep the original programming log — the X431 can save a PDF report of the session. Store it with the vehicle’s service file.
5. If unsure, call LAUNCH support — they offer remote assistance for IMMO Elite users. A 15-minute call can save hours of frustration.

Frequently Asked Questions

Can I program just one key in an All Keys Lost situation?

Yes, but you must still erase all existing keys first. You can then add a single key, but programming only one key leaves no backup — if it fails, you're stranded. Two keys are strongly recommended.

Do I need the security code (PIN) for every Bentley Bentayga?

Yes. The immobilizer demands a 5-digit PIN. You can obtain it online via X431's IMMO Elite service (requires payment per VIN) or from a Bentley dealer with proof of ownership. Without the PIN, you cannot enter the security access step.

My X431 says "Function Not Supported" for the Bentayga – what now?

Your X431 likely lacks the IMMO Elite subscription or the software is outdated. Update via Wi-Fi, then purchase the IMMO Elite add-on (yearly or per-use license). Basic IMMO functions on X431 do not cover all-keys-lost for high-end brands like Bentley.

Can I use aftermarket blank keys from Amazon?

It is highly discouraged. Bentayga keys have complex encrypted chips (4D70/80). Non-OEM blanks often fail programming, leaving you with a key that turns the lock but won't start the engine. Always use OEM blanks from a locksmith or dealer. For more on selecting the right blanks, check out our guide on [understanding transponder key types for luxury vehicles] — placeholder link.

How long does the entire process take?

Allow 30–60 minutes including setup, PIN retrieval, programming, and testing. If you hit issues (e.g., PIN lockout), it can extend to 2+ hours. Always schedule enough time — rushing increases the risk of errors.

What if I lose connection mid-program?

DO NOT turn off the ignition. Reboot the X431 and reconnect to the vehicle using the same IMMO session. The ECU may still be in "learn mode" for a few minutes. If you turn the ignition off, the ECU locks, requiring a dealer visit. To avoid this, also read our article on [preventing ECU lockouts during key programming] — placeholder link.

Does programming affect the vehicle’s other computers (e.g., transmission, air suspension)?

No. Key programming only touches the immobilizer (KESSY/BCM). Other modules are unaffected. However, disconnecting the battery (improperly) can cause unrelated faults — keep the battery maintainer connected throughout.

Is there a risk of bricking the ECU?

Yes, especially if you repeatedly enter wrong PINs, interrupt the erase cycle, or use incompatible key blanks. If bricked, the ECU must be replaced and programmed by a Bentley dealer (costly: $2000+). Proceed with caution. For a deeper dive into immobilizer security, see our piece on [Bentley BCM architecture and recovery options] — placeholder link.

Disclaimer: This guide is for informational purposes. Always verify compatibility with your specific X431 version and Bentayga model year. If you are not experienced with advanced immobilizer programming, seek professional assistance.

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.

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