Found this online and thought since I had this problem, it could be useful here.... 2004-9 Prius Keyfob Battery Change Edit: Link is broken. See part number in next post.
I just replaced the battery in each of our two fobs. The posted instructions really helped. I would only add that it was important to try pushing the back off slightly, just a little movement before you press down on the latch. I noticed that without pushing the latch down, a little movement can be seen / felt. after that slight movement, the pressing down of the latch then seemed to release the cover easier than trying to slide the cover off while pushing down the latch. The reason I changed them was because I sometimes hear a single beep when powering down the vehicle. Sometimes it beeps once, and other times it would not. since I buy a bunch of these batteries towards year end, I thought why not replace them both since I have them laying around. I used an Energizer CR 2032 3V battery. The old ones were not dead yet, but the distance that I could use them from away from the vehicle seemed to be getting shorter. The old batteries were checked on my battery checker and while still in the green, they were approaching the red replace zone on the meter. If anyone knows what that occasional single beep is on power down, I would like to know.
I just wanted to add that the single beep on power down has not happened since I replaced the key fob battery. The car has been driven three times since I replaced it.
So my cover was really tight after 6+ years and my hands not strong enough even using all the helpful tips given. But - look carefully at the latch area to see where the cover and base sections connect. You can put the tip of your small screwdriver into the latch area cutout and apply leverage against the base to get the cover moving. The rest is as already described.
I too had beeps when powering down my 2006 prius with SKS but didn't think much of it. Just today I could not get into my car without using the spare physical key. When I got inside, pressing start showed that the Key was Not in the Car symbol. I pushed the keyfob into its hole and the car was able to start. When I got home I replaced the battery with the same make/model but when I went outside to try it, the same issue happened as described above. Question: Do I have to tell the car that the keyfob is working again? If so how? I should not have to reprogram it right? The FOB light now blinks when I press lock/unlock, but again the car does not reconize it. Please help. Thanks.
I leave the screws out of the back of mine. The way it locks together the screws are not necessary (for the next battery change out).
It's possible you've disabled the sks. Look under the steering wheel for a button and push it in. From John's site Automatic Disable [FONT=Times New Roman,Times New Roman][FONT=Times New Roman,Times New Roman]Leaving the FOB inserted into the dashboard-slot for more than 10 minutes after power OFF will cause the SKS to be disabled. To enable it again, press the button under the steering-wheel. [/FONT][/FONT] Manual Disable [FONT=Times New Roman,Times New Roman][FONT=Times New Roman,Times New Roman]Look for a button labeled "SMART" on the dashboard directly underneath the steering-wheel. Pushing that will toggle between disable & enable. As the 12-volt auxiliary battery ages, constant trickle drains from it for extended durations (especially during the winter) should be avoided. So if you are going to leave your Prius sit for several weeks, the disable will help you get the longest life from the battery. Note that the battery-pack, not the auxiliary, is what supplies power for starting the engine. [/FONT] [FONT=Times New Roman,Times New Roman]Another use for that "SMART" button is to simply prevent the wireless functionality, should you have the need for direct-contact only operation. [/FONT][/FONT]
The SKS is a tricky thing. After install the new batt, I could not get the unit to sync up with the car. It would not unlock the doors or anything. About an hour later I tried again, and everything works. Guess it need some time to find each other. How romantic...
just wanted to reinforce this. my key fob cover would not budge *at all* - until I inserted a small tool underneath the latch from the side (with the latch retracted all the way) and pried the latch w/ cover out the end. the tool I used was the awl of my swiss army knife and it worked great as I'm sure a small flat screwdriver would
Hello, thanks for the instruction. I want to add some based on my experience. I notice if I just push the case horizontally, I couldn't open the case, but if I pushed the case with a little bit slope, it is opened easily. Since my finger is too fat, I used the prius key to lift it with some angle like 1-2 degree.