How to Replace the Key Battery for Mercedes-Benz S350?
4 Answers
The back of the key has a button. Press this button and push the back cover of the key forward to open it, then replace the battery directly. Below is the related content introduction: Model Introduction: The Mercedes-Benz S350 is produced by the German Daimler-Benz company. The most significant improvement in the 2004 new-generation S350 lies in the brand-new V6 engine from Mercedes-Benz. The 3.7-liter engine's output power increased by 12.5% compared to the previous generation V6 engine, reaching 180Kw (245Hp); torque improved by 13%, achieving 350Nm at 3000rpm.
As a DIY enthusiast, replacing the battery in a Mercedes S350 key is quite simple. First, prepare a CR2032 coin cell battery, which costs just a few dollars at supermarkets or online. On the back of the key, there's a small notch—use a plastic pry tool or a small coin to gently open the casing, avoiding metal tools to prevent scratches. Once open, remove the old battery, paying attention to its orientation: the positive side faces up, so make sure not to insert the new battery backwards, or the key won't work. Then, close the cover and press all edges firmly but gently. Next, test it: stand near the car and press the unlock button to see if the light flashes, or try opening the door and starting the car. The whole process takes just a minute or two. The battery lasts one to two years; if the car warns of low battery or the key responds slowly, replace it promptly to avoid being locked out. The key casing is made of brittle plastic, so handle it carefully to avoid breakage and costly repairs. Keep the key in a dry place like a bag to prolong battery life.
Safety first when performing the operation, as Mercedes key fob components are fragile. Prepare a new CR2032 battery and plastic tools. Locate the seam on the key, gently pry open the casing, and wear gloves to avoid static electricity. The old battery may be toxic, so don't throw it in the trash casually; it should be recycled. When installing the new battery, remember to place it with the positive side facing up, then firmly close the cover. Test the functionality immediately, such as pressing the lock button or starting the car by proximity. If it doesn't work, the contacts might be dirty—clean the copper pieces with a cotton swab dipped in alcohol. If you're unsure, a professional repair shop can do it quickly and safely for just a small labor fee. The interior of the key is delicate; prying too hard could break the clips, requiring a whole new key replacement, which is costly. I recommend checking the battery regularly: replace it after a year of use or at the first sign of weak performance to avoid getting stranded.
Replacing the battery in a Mercedes S350 key is not difficult. Purchase a CR2032 battery, locate the seam on the key, and use a fingernail or small coin to pry open the casing. Remove the old battery, note its orientation, and insert the new battery in the same direction. Close the cover firmly and immediately test the unlock and start buttons. The entire process takes about a minute, and batteries can be bought at supermarkets. Handle the key gently to avoid dropping it or dirtying the contacts. If you find it challenging, watching an online tutorial video can be very helpful.
