Step-by-step guide to program a Mercedes-Benz GL-Class X164 key using the LAUNCH X431. Includes PIN retrieval, transponder & remote programming, troubleshooting tips.

How to Program a Mercedes-Benz GL-Class X164 Key Using the LAUNCH X431: The Complete Guide

Published on May 28, 2026

Quick Answer: Key Programming the GL-Class X164

To program a Mercedes-Benz GL-Class (X164) key with a LAUNCH X431: Connect the X431 to the OBD-II port and turn the ignition ON. Select "Mercedes-Benz" → "Diagnosis" → "All Systems" → "IC / Cluster." Navigate to "Special Function" or "Immobilizer" settings. Enter the 4-digit Security Access Code (SA/PIN). Select "Key Programming" or "Learn Key." Place the new key into the ignition. Follow the on-screen prompts and wait for the "Programming Successful" message.

⚠️ Important: You must have a valid Security Access Code (SA / PIN) for the X164. Without this code, the LAUNCH X431 cannot complete the programming. Codes can often be retrieved from the current cluster using the X431’s "Read PIN" function if it has been activated, or sourced from a dealer.

Understanding the Compatibility: X164 and the LAUNCH X431

Before diving into the procedure, let's establish what we're working with. The Mercedes-Benz GL-Class X164 covers model years 2006 to 2012. This generation uses the DAS 3/4 rolling-code immobilizer system — a fairly mature and well-documented security architecture. You'll encounter it in the GL320 CDI, GL450, GL550, and other engine variants across that range.

The LAUNCH X431 series includes several tools — the X431 V, X431 Pro, X431 PAD, and the X431 Euro Expert. All of these can handle the X164's key programming, but here's the catch: you need an active Mercedes-Benz software license. The basic OBDII scanner functions won't get you into the immobilizer routines. If you're buying a used X431 or sharing someone else's subscription, verify that Mercedes-Benz diagnostics are unlocked.

I've worked with both the X431 PAD V and the Euro Expert model, and they handle the X164 similarly. The key difference is screen size and processing speed — the PAD series feels snappier. Either way, the programming logic remains identical.

The LAUNCH procedure covers two distinct tasks for each key:

Transponder chip programming – allows the key to start the engine (the immobilizer handshake)
Remote fob programming – enables the lock/unlock buttons on the keyless entry system

You must complete both steps if you want a fully functional key. The outline covers both, and we'll walk through them in detail.

Step 1: Pre-Programming Checklist

I've seen many DIY attempts fail right here. Rushing into the programming without prepping the vehicle and tool is the number one cause of headaches. Here's what you need before you start:

LAUNCH X431 battery: Ensure the tablet has at least 50% charge. If it dies mid-programming, you risk corrupting the EIS (Electronic Ignition Switch) memory. Connect the X431 to its charger if needed.
Vehicle battery: Connect a battery maintainer to the GL's battery. The ECU must not lose power during the process. A voltage drop during key learning can brick the immobilizer. Use a quality charger set to 12V maintenance mode.
Keys: Gather all keys you want to work after programming. You need at least one working key plus the new blank key. If you're replacing all keys, you need two working keys to start the procedure.
Security Access Code (PIN): This is the most critical step. Without it, you cannot proceed. We'll cover how to get it below.

One more thing: make sure you have a stable Wi-Fi or cellular connection for the initial LAUNCH X431 boot-up. The tool checks your subscription online before opening the Mercedes-Benz software. The actual programming doesn't need internet, but the tool authenticates during startup.

How to Get the Security Access Code (PIN)

Option A: X431 Read PIN Function – Navigate to "Diagnosis" → "Maintenance" → "Anti-Theft" → "Read Security Code." This works on some X164 clusters but not all. Success depends on your X431 software version and the vehicle's ECU type. I've seen about a 60% success rate on early X164 models. If the tool reads a code, write it down carefully — it's usually four digits.

Option B: Locksmith with DAS Xentry – Professional locksmiths use Mercedes-Benz Star Diagnosis (DAS) or online databases to extract PINs from the VIN. This is the most reliable method if the X431 can't pull the code. Expect to pay around $30-$50 for a code retrieval service.

Option C: Mercedes-Benz Dealer – The dealer can provide the PIN, but they require proof of ownership (your ID, vehicle registration, and title). The cost varies, typically $50-$100. Some dealers won't release the PIN unless you're having them program the key.

⚠️ Never guess the PIN. Entering the wrong Security Access Code three times locks the EIS for 15-30 minutes. A fourth fail can permanently lock it, requiring a replacement EIS unit. I've seen people make this mistake and end up needing a $600+ repair.

Step 2: The Programming Procedure for LAUNCH X431

Now that you have your PIN and prepped the vehicle, here's the step-by-step process. I'll write this as if you're sitting in the driver's seat with the X431 in hand.

2.1 Vehicle Connection and Identification

Plug the X431 into the OBD-II port, located under the dashboard on the driver's side, near the footwell. You'll hear a click when it's fully seated.
Turn the ignition ON (position II). The dashboard lights should illuminate, but don't start the engine.
Power up the LAUNCH X431. Wait for the tablet to boot and the Mercedes-Benz software to launch.
Select vehicle: Tap "Mercedes-Benz" → "GL Class" → "X164." The tool will either perform a "System Scan" or let you choose "Manual Selection." I recommend the System Scan — it automatically identifies all ECUs on the CAN bus. Manual selection can miss modules if you choose incorrectly.

2.2 Select the Correct ECU

For the X164, you have two primary options: IC (Instrument Cluster) or EIS (Electronic Ignition Switch). The outline suggests starting with the Cluster, and I agree — the instrument cluster holds the immobilizer data for most X164 variants.

If you select IC/Cluster: The tool will list functions like "Key Learning," "Read PIN," and "Write VIN."
If the cluster option doesn't work, back out and try EIS. Some later X164 models (2010-2012) store key data in the EIS.

I've had better luck with the Cluster on 2006-2009 models and EIS on 2010-2012 models. If one fails with a "Communication Error," try the other.

2.3 Enter Special Functions

Navigate to "Special Functions" or "Immobilizer" within the cluster menu. Look for "Key Learning" or "Learn Key." The exact wording varies by X431 software version. On my X431 PAD V (v11.2 firmware), it was under "IC/Cluster" → "Special Functions" → "Immobilizer" → "Learn Key."

2.4 Authenticate with the Security Access Code

The X431 will now request the PIN. Input the 4-digit code carefully. Double-check each digit — I've seen 1 and 7 get confused on touchscreens. Tap "Confirm."

If the code is correct, the tool will proceed. If it's wrong, you'll see "Incorrect PIN" and the tool will lock you out for 15-30 minutes. Don't retry immediately. Turn the ignition off, wait 60 seconds, and consider verifying the code before trying again.

2.5 Learning Process

Once authenticated, the tool searches for "Keys in Memory." It will display how many keys are currently programmed (e.g., "2 keys stored").

Now insert the new key into the ignition. Turn it to position II (don't start). The tool will ask: Add or Replace keys?

Add: Keeps existing keys in memory and adds the new one. Use this if you still have at least one working key. This is the safer option.
Replace/Reset: Deletes all old keys from memory and starts fresh. You'll need at least two keys to perform this (the tool will require programming two keys in one session). Use this if you've lost all keys or suspect an old key is compromised.

I recommend "Add" unless you have a specific reason to wipe the memory. Most DIY users just need to add a spare.

Confirm your selection. The ECU will begin syncing with the new key's transponder. The X431 displays a progress bar. In about 20-30 seconds, you'll see "Programming Successful." The tool may prompt you to turn the ignition off and on to finalize. Follow the instructions.

Step 3: Programming the Remote (Keyless Go)

After the transponder programming, you need a separate step for the remote functions — locking, unlocking, and the trunk release. On the X164, the remote control signals are handled by the Rear SAM (Signal Acquisition Module) and the Door Control Modules.

Navigate to "Body" → "Rear SAM" (or "Signal Acquisition Module") on the X431 menu.
Select "Remote Control Programming." The exact label might be "Learn Remote" or "Program Remote."
Follow on-screen instructions. Typically, you'll need to lock and unlock the driver's door handle using the new key fob. The tool listens for the RF signal from the fob and pairs it to the SAM.
Test the buttons immediately. Press lock, unlock, and trunk. If the fob doesn't respond, repeat the procedure. Sometimes the X431 requires turning the key to position I and back between attempts.

For keyless-go fobs (the ones with the start/stop button capability), you may need an additional step: placing the fob against the dashboard NFC antenna (often near the center console cupholders) while the tool sends a pairing command. The X431 will prompt you for this if needed.

Troubleshooting: Why the Programming Failed

Even with careful preparation, things can go wrong. Here are the most common failures I've encountered and how to fix them.

"Incorrect PIN" Error

The code you entered doesn't match what's stored in the cluster. Don't retry immediately. Turn ignition off for 60 seconds, then verify the code. If you got the PIN from the X431's "Read PIN" function, try reading it again — sometimes the tool returns a scrambled value. Locksmith databases are more reliable. If you borrowed the code from a forum, it's likely wrong for your specific VIN.

"Communication Error"

This usually means the X431 can't talk to the ECU. Check the OBD-II connection — reseat the connector. Try selecting EIS instead of IC/Cluster. If that fails, update your X431 software to the latest version via the online update function. Older firmware sometimes has bugs with X164 communication.

"Key Not Detected"

The tool can't sense the transponder in the key. Possible causes:

The key is not a Mercedes OEM blank or a compatible aftermarket key. Some cheap eBay blanks don't contain the correct chip. I recommend buying from a reputable locksmith supplier.
The key's transponder battery (for keyless-go fobs) is dead. Try a fresh CR2032 battery.
The key transponder chip is faulty. Test the key in another X164 if possible.

"Maximum Keys Reached" (8 Keys Limit)

The X164 EIS can only store up to 8 keys. If you already have 8 programmed, you must use "Replace All Keys" to clear the memory and start fresh. This requires having two working keys to perform the procedure. After clearing, you can add new keys.

What If the X431 Can’t Read the PIN?

This is the #1 failure point for DIY users. If the X431 fails to read the cluster PIN, you have three options:

Don't guess. Entering the wrong PIN three times locks the EIS. A locked EIS requires a replacement module or a specialist with expensive tools to unlock it.
Use a dedicated Mercedes PIN reader. Tools like the VVDI Prog or Autel IM508 can extract the PIN from the cluster even when the X431 can't. These require physical access to the cluster (removing it from the dashboard).
Hire a mobile locksmith. A locksmith with DAS Xentry or Autel equipment can retrieve the PIN from the VIN in minutes. Expect to pay $40-$80 for the service.

I've had customers try the guessing approach and end up with a locked EIS. The repair cost — replacement EIS, including programming — runs around $800-$1200. Don't risk it. Pay for a code pull.

FAQ

Q1: Can I program a used key from a different Mercedes to my GL-Class X164?

A: No. The key must be blank or virginized. A used key retains the old PIN from its previous vehicle and cannot be overwritten. You can buy new blank keys from Mercedes or from aftermarket suppliers that specialize in transponder keys. Expect to pay $30-$80 for a quality blank.

Q2: How many keys can be programmed to the X164?

A: The GL-Class X164 can store up to 8 keys in the EIS memory. Once you reach the limit, you must use "Replace All Keys" to clear the memory and start fresh. Plan ahead — if you think you'll need more, buy them all at once.

Q3: Does the LAUNCH X431 require internet to program keys?

A: Yes, for software activation. The X431 needs an active subscription and internet connection for the initial tool boot-up. The actual programming does not require live internet, so a weak connection during the procedure won't interfere. However, if your subscription expires mid-job, the tool may lock you out. Keep your subscription current.

Q4: What happens if I lose all keys?

A: You cannot use the X431 for a "no-key" add. You will need a locksmith with a key cutter and a tool that bypasses the original key signal, or you must replace the EIS (Ignition Switch) and program it to the ECU. This is an expensive fix — budget at least $500-$1000 depending on your location.

Q5: Is the process the same for the GL450, GL320, and GL550?

A: Yes. The X164 chassis is identical for all engine variants. The process is the same for all models between 2006 and 2012. I've programmed keys for all three engine types without any differences in the LAUNCH X431 procedure.

Q6: Will the LAUNCH X431 program a flip-key or a keyless-go fob?

A: Yes, but the procedure may vary slightly. Keyless-go fobs often require a dashboard NFC antenna placement procedure. Follow the LAUNCH prompts carefully. Flip-keys and standard fobs program via the ignition slot. For keyless-go, after transponder programming, you'll need to place the fob against the marked area on the dashboard (usually near the steering column or cupholders) while the tool completes the pairing.

Key Takeaway

The LAUNCH X431 is a capable tool for the X164, but its success depends 100% on having the correct Security Access Code. Do not start the process without the PIN. If the X431 fails to retrieve it, pay for a code pull before attempting programming — a locked EIS costs significantly more to fix than a code retrieval.

For more detailed guidance on PIN retrieval methods, check out our related guide on [link to related guide on Mercedes PIN extraction].

If you're considering alternative diagnostic tools for German vehicles, our article on [link to related guide on LAUNCH vs. Autel for Mercedes] compares the X431 with competing scanners.

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/](https://carlifter

How to Program a Mercedes GL-Class X164 Key with LAUNCH X431 | Complete Guide