How to Replace the Key Battery for a Mercedes-Benz Car?

[SanArya]

Steps to replace the key battery for a Mercedes-Benz car: 1. Select a new button battery that matches the specified model; 2. Push the switch at the tail of the key upwards to eject the mechanical key, then remove the mechanical key; 3. Use the extracted mechanical key to press against the notch, gently pry outward to open the key casing; 4. Remove the old battery, replace it with the new one, ensuring the positive and negative poles are correctly aligned. Mercedes-Benz models include the E-Class, S-Class, GLS, B-Class, etc. Among them, the E-Class has a body size of 5021mm in length, 1854mm in width, 1487mm in height, and a wheelbase of 3014mm.

[OConnor]

As a Mercedes-Benz owner, my experience changing the key fob battery was straightforward. My key has two or three buttons – just use a coin or small flathead screwdriver to gently pry open the casing by inserting it into the side seam. Remove the old round coin-shaped CR2025 battery (double-check this size when buying replacements). When installing the new battery, ensure correct polarity (usually ‘+’ side faces up). Carefully snap the casing back together until you hear a click. Test remote locking/unlocking functions afterward. Mercedes key batteries typically last 1-2 years – replace proactively when dashboard warnings appear to avoid being stranded. DIY replacement saves dealership trips and costs under $2 for quality batteries. Keep contacts clean and avoid moisture (I once had key failure due to leakage corrosion). The whole process takes about a minute – apply minimal force to avoid damaging plastic components. Regular maintenance extends key life, and Mercedes designs these for user-friendly servicing.

[MadisonAnn]

As a car enthusiast, I often help friends replace the battery in their Mercedes keys. There are various key types, and some with smart buttons need to be pried open from the side—look for the small notch. You can use a thin key or a coin as a tool, but be gentle to avoid scratches. The battery model is usually CR2025, which can be easily purchased online or at supermarkets. When installing, pay attention to the electrode direction—the positive side should face upward and align with the contacts. After reassembly, test if the remote control distance is normal. Mercedes batteries typically last 1-2 years; when they’re running low, you may notice sluggish remote response, so timely replacement is crucial. Also, be careful with the waterproof rubber ring inside the key—don’t lose or deform it when removing the old battery. After replacement, test starting the car—no programming is usually needed since the Mercedes system can recognize it automatically. DIY battery replacement is super simple, costing less than 20 yuan, much more cost-effective than visiting a repair shop. Plus, you’ll learn a few handy tips—keep your tools clean and have a spare battery just in case.

[AuroraFitz]

As a young car owner, I found it surprisingly easy to replace the battery in my Mercedes key for the first time. Just find a small gap on the key, gently pry it open with a coin or fingernail—don't force it or the shell might break. Then take out the old battery and put in the new one, making sure it's the round CR2025 model, with the plus side facing up before pressing it in. After assembly, test the remote functions to ensure they work. The Mercedes dashboard will give a warning light before the battery dies. DIY replacement saves money and is quick—even beginners can handle it. Keep a spare battery in the car for emergencies, avoid water or grease during replacement, keep everything clean, and the whole process takes just minutes. Regular checks can extend battery life.