2018 Mercedes-Benz Sprinter Key Fob Programming Guide

As an ASE-certified electrical technician and automotive locksmith, I frequently get questions about Mercedes-Benz keys. The 2018 Mercedes-Benz Sprinter is an incredible workhorse, but when it comes to key fob programming, the German engineering that keeps the van secure also makes replacing keys a highly specialized process.

Unlike older domestic vehicles, your 2018 Sprinter utilizes the Mercedes-Benz Drive Authorization System (DAS), meaning DIY programming is completely locked out. Here is everything you need to know about replacing, programming, and maintaining your 2018 Sprinter key fob.

Quick reference

Step-by-step on-board programming

If you are looking for a sequence of pedal presses or ignition turns to program a new key fob for your 2018 Mercedes-Benz Sprinter, I have to stop you right there. There is absolutely no on-board DIY programming procedure for this vehicle.

Mercedes-Benz uses a highly secure, encrypted immobilizer system (often FBS3 or FBS4 on this era of Sprinters). The key communicates via infrared (IR) and radio frequency (RF) with the Electronic Ignition Switch (EIS/EZS).

Because of this encryption, you have two options for programming a new key:

1. The Dealership: The dealer will order a "virgin" key pre-programmed to your specific VIN from a regional Mercedes-Benz hub. Once it arrives, they may need the van present to sync the rolling codes, but often the key simply works in the ignition right out of the box because it was coded at the factory.
2. Advanced Automotive Locksmith: A specialized locksmith with high-end diagnostic tools (like the Autel IM608 or Xhorse VVDI MB) can read the EIS data directly from the vehicle and generate a dealer key on the spot using a blank aftermarket fob.

Battery replacement

While you cannot program the key yourself, replacing a dead battery is a very simple DIY task. If your Sprinter isn’t recognizing the key or the remote range has diminished, try this first:

1. Locate the sliding locking switch on the bottom of the key fob.
2. Slide the switch and pull the metal emergency key blade out of the fob.
3. Look into the slot where the mechanical key was housed. You will see a small gray latch or tab.
4. Use the tip of the metal key to gently press that inner tab sideways while simultaneously pushing upwards on the back cover of the key fob.
5. The battery cover will pop off.
6. Remove the old battery and insert a fresh CR2025 battery, ensuring the positive (+) side is facing up.
7. Snap the battery cover back into place and reinsert the emergency key blade.

Where to buy a replacement fob

Choosing where to source your replacement Sprinter key comes down to your budget and timeline.

• The Dealership: This is the safest, most guaranteed route for Mercedes-Benz. You will need to provide proof of ownership and your ID. Expect to wait a few days for the key to be ordered and shipped from the manufacturer. Pros: Guaranteed OEM quality, no risk of incompatible parts. Cons: Very expensive. Expect to pay between $350 and $600+ for the key and sync.
• Automotive Locksmith: A qualified European auto locksmith can supply and cut/program an aftermarket or refurbished OEM key on the same day. Pros: Fast turnaround, usually cheaper than the dealer (typically $250 to $450). Cons: You must find a locksmith specifically equipped with Mercedes-Benz key programming tools.
• Amazon / Online Retailers: You will see empty key shells and uncut/unprogrammed aftermarket fobs online for $20 to $50. Pros: Very cheap upfront cost. Cons: Most locksmiths will refuse to program a customer-supplied Mercedes key. Many cheap online keys have low-quality IR components or the wrong frequency. Furthermore, a used Mercedes key from eBay cannot be reprogrammed to your van unless it has been properly "renewed" or "unlocked" by a professional.

If on-board programming isn't supported

As mentioned, on-board programming is impossible due to the vehicle's immobilizer transponder system. The Sprinter uses a complex Electronic Ignition Switch (EIS) that verifies an encrypted hash with the key before it releases the electronic steering lock (ESL) and allows the engine control unit to fire the injectors.

If you lose all of your keys (an "All Keys Lost" situation), the cost and complexity go up significantly. A locksmith will have to either remove the EIS from the dashboard to extract the password data on a bench or use advanced OBD2 methods to calculate the password online. Always try to keep at least one spare key on hand to avoid these massive headaches!

If you need a new key made, don't waste time trying DIY sequences that will only frustrate you. Find a mobile locksmith or shop on Repairius.