How to Replace the Battery in a 2002 Toyota Sienna Key Fob

If your car key fob isn't working well, the battery more likely needs to be changed. In this post, we described how to disassembly your car keyless entry remote and replace your Toyota key battery.
What size battery does 2002 Toyota Sienna remote key fob required
Before starting open keyless entry remote check all that you need: flat head screwdriver, phillips head screwdriver and 1xCR2025 battery.- flat head screwdriver
- 1xCR2025 battery
- phillips head screwdriver
Step by step guide
A button cell battery installed inside the your remote key fob. Remove screw on the back of the key fob. Spin the keyless entry remote over and find for at least 1 screw holding in the plastic.
Delicately try to disassemble your key fob with pry tools. Change 1 CR2025 battery with flat head screwdriver.
Replace old battery with new one CR2025. Be sure to connect the battery the right way around in a circuit. Your key will not work if you put battery wrong way.
Before assembling keyless entry fob's case, verify that all working fine by testing buttons on circuit board.
The last thing to do is put your cover back on fob. Carefully try to assemble the two halves in place by hands from top to bottom. Check your key case for gaps. If it is not firmly closed try to repeat last step. Screw the back of the remote key fob.
Video of key fob disassembly
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