How to Change the Key FOB Battery
2004-2009 Toyota Prius
This job has been documented before as it's straight out of the Prius Owner's Manual (pg 392 for my 2009) but I wanted to document my take on the job for site completeness; especially since my "new" 2009 just started giving me the indications the key battery needs replacement. What are those? Well, after shutting off the car it beeps at you, range may be reduced and it may not function at all. I also noticed the security "key" icon flashing on my dash after shutting off the car. In other words, the car has multiple ways to tell you to replace the FOB battery. Since there is no mechanical key to start the car you'll want to swap this battery as soon as you notice any signs it's getting weak. It looks like original batteries are made by Panasonic as that's what has come out of both my '08 and '09 Prii key FOB's. I'd say a 3-5 year lifespan, not too bad.
- Precision screwdrivers, Philips #0 at minimum
- Thin flat-head screwdriver / paperclip
1) With the FOB buttons facing up, slide the spring-loaded holder to the left (RED) and while doing this pull the key up and out (BLUE).
2) With the FOB buttons facing down, slide the spring-loaded holder to the right (RED) and while doing this push the back panel up (BLUE), it should slide right out. If this doesn't easily slide off try using a rubber glove to get additional grip on the FOB.
3) Remove the 4 screws circled in RED using a philips #0 screwdriver. Then use a paperclip or thin flat-head screwdriver to pry up the battery cover plate, the BLUE arrow is where you can pry from.
4) Swap out the CR2032 battery, the positive (+) side faces the cover panel. Assembly is reverse of removal.
- Toyota Prius Owner's Manual
- Prius Key FOB Transmitter by Luscious Garage
- Random YouTube video on FOB battery replacement:
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