How to Replace the Battery in a 2008 Mercedes-Benz S550 Key Fob

Remote key fob allow access to your S550. When the key fob battery is discharged you lose your fob’s ability to use remote opening function. In this article, we are going to tell you how to open your keyless entry remote and replace a dead or weak battery yourself. If you decide to do it at home near S550, use this instruction, but first make sure you have everything you need.
What size battery does 2008 Mercedes-Benz S550 key fob take
Before going to disassembly keyless entry remote make sure that you have all required tools and materials: flat head screwdriver and 2xCR2025 batteries.- flat head screwdriver
- 2xCR2025 batteries
Step by step guide
A button cell battery installed in the your keyless entry remote. Move the key out of the way if it is in the remote key fob.
Carefully try to open your key with pry tools. Remove CR2025 batteries with flat head screwdriver.
Change old batteries with new one CR2025. Every battery has a negative and positive side and if you put the wrong connector down, the charge cannot go into your circuit board and make it work. Check position on battery, by "+" mark.
Before assembling keyless entry fob's case, make sure that all functions works by testing buttons on remote key fob.
The last thing to do is put your cover back on fob. Accurately try to put the pieces together by hands from top to bottom. If your fob body tightly closed, we done. If not, repeat the last step.
Video of key disassembly
Mercedes Key Fob Battery Change Replacement Chrome Key by MercedesMedic.com round panic
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