How to replace your Key Fob battery on a 3rd Gen Prius

Good to know. Thank you!

 

Even with a dead transmitter battery you can get the car to start by placing the transmitter up against the start button until the light illuminates, then hit the button.

 

You don't need a flat head screw driver, you can use the key to pry it on the side. It is the same exact size for that hole.

 

Hmm...

Seems like a lot of prying, around very fragile tabs, plus the removal and flipping of the entire circuit board, just to change the battery?

Doesn't strike me as the most user friendly design.

 

Someone should make this is a sticky.

 

I think Toyota did. They stuck it in your owners manual. Page 460 for 2013. That way you can keep it in your car so you will always have it when you need it.

 

It's not fragile at all since they made it strong enough to be removed so that you can replace the battery.

 

Still think it's not very user friendly. Having to use a small screwdriver and actually remove the circuit board and flip it, just to change the battery doesn't seem very well designed. And some of those tabs look pretty fragile to me. Glad it's something that doesn't have to be done very often.

 

you don't need a screw driver to pry open anything. The key FOB has everything built in to remove and replace the battery by hand. I've done it before so I know.

Unlike the Honda key FOB where you need a Philip screw driver, the Prius key FOB is much easier in my opinion. If you need me to make a video of it, I'll make one tomorrow and post it after and show you

 

Just as DYNASTY demonstrated, very simple process. I had my battery changed after 2 low battery warning, didn't want to wait for complete failure. Took it to a local RADIOSHACK and they replaced it in a few minutes. I even had them check the voltage on the old battery, and it was low. I used the key fob for about 3 1/2 years before replacement. cost about $5.

 

2 dollars for 2 on ebay

 

Sure it's an easy process, when the guy at Radioshack does it for you.

I'm not saying it's impossible, rocket science or brain surgery. I think I could do it.

But I am saying, I think Toyota could of designed the entire fob, with something as basic as a battery access panel. That would of made the whole process a lot easier than having to basically disassemble the whole thing, pry fragile tabs and flip the circuit board.

 

My dealer changed my battery for free, never hurts to ask.

 

Based on experience with a Toyota Camry, expect to replace the battery every two years in order to assure reliability. However, I waited on the primary FOB battery to die before replacing it with a new one. Compared to my old BMW FOB, Toyota has made the battery replacement very easy. Also, you should not store the FOB near electronic devices such as mobile phones, as the devices will cause battery drain on your FOB.

My new Harley has an active security system that requires the use of a FOB near the bike, but no key is required to start the motorcycle. If your FOB is left at home and you ride off, you must use a start procedure using several steps including an owner selected code. Overall, the system appears to be overly complicated. But, I'll take the insurance discount. My Harley dealer said to replace the battery every year. Hopefully, the battery will last at least two years.

 

One of mine started alarming last week, I have had the car for 3 yrs 10 mo. I replaced them both. Bought the batteries at Wal Mart for $5.95 ea.

 

Thank you for posting this Dynasty! When my first fob battery died I took it apart to extract the battery and found nothing (because it was obscured by the circuitboard). Talk about a head scratcher. Why would Toyota expect that people would be comfortable with prying off a circuitboard is beyond me. Most are glued/riveted into place and cannot be reassembled if pried (broken!) off. They should have designed it so the battery was just there waiting for you when you opened up the fob - that's what people are used to.
Yeah, I know, preaching to the choir...

 

I think maybe they wanted the fob to be as water tight as possible one less opening to leak around. Notice the thin water tight gasket in the fob. A friend of mine has put the fob thru the wash cycle twice now, no problems. Just a nutty guess!

 

When I did ours I first tried the tip of the embedded key, and while was the right width, something didn't feel "right", it just didn't have enough leverage. Finally settled on a similar, broad bladed screw driver. Width is good, to avoid stressing the case. And as I recall, the clips on the battery are finicky/fragile.

 

I'm uploading the video on how to do this as we speak right now, it takes less than 1 minute to do and does not require any special tools. I will post it once its up.

Here it is!