Key Fob

I have an '04 and yes, I replaced the batteries about a year ago. I had it done at the dealer but I believe there is a detailed explanation of how to do it yourself in the owner's manual.

 

It is in fact in the owners manual and it is real easy to do. There is a little latch you push over to remove the mechanical key; you have to hold it over to get the back cover off also. Under the back cover are 4 very small phillips screws, take them out and you will be where the battery is. Get the O ring back in right or it won't be water proof any more.

 

<div class='quotetop'>QUOTE(artie @ Jul 28 2006, 05:18 PM) [snapback]294070[/snapback]</div>

Like usual they are full of it!

The LED takes a minute amount of voltage to function. It has nothing to do with the actual functioning of the remote. I have installed hundreds of car alarms, and thousands of remote batteries. Almost always the LED still functioned when the remote did not.

Change the batteries. In fact, I would change them yearly, just to prevent this type of issue down the road. And as far as heat...yes it can have an effect...but a lot of us keep our keyes in our pockets...and it is pretty hot and humid in a pocket!

 

I agree with Mike. The fob battery is cheap and the procedure is simple, compared to the hassle of not being able to open the door or start your car. Change your fob battery regularly. Based on the evidence, every year.

 

Well, I accidentally dropped the key fob in the water and still works perfectly. The thing must be water proof.

 

<div class='quotetop'>QUOTE(Mr. Tuco @ Jul 29 2006, 02:36 AM) [snapback]294247[/snapback]</div>

One guy reported leaving his fob in his pants pocket and sending it through the clothes washer (by mistake) and having no problems. Waterproof, yes, infinite battery life, no.

 

<div class='quotetop'>QUOTE(mssmith95 @ Jul 28 2006, 09:48 PM) [snapback]294183[/snapback]</div>

Do we have to decipher what “it” is? :huh:

I agree with the dealer - therefor I believe the “it” refers to them being full of knowledge. :lol:

The little red light – ON THE KEY FOB ITSELF (located to the right of the lock button) – will only flash when the key is properly interrogated by the car and proper signals are sent back and forth. If you don't believe this, take both of your key fobs in one hand with the LED lights facing you, then walk up to the front driver or passenger door. Only one key will flash. The other key remains silent, dumb – whatever.

If, on the other hand, you push one of the buttons on the key fob, the LED will flash if a proper signal is being sent – within range of the car or not. It is the key fob's electronics which tell the LED light to flash, not just the voltage level of the battery. If you have a weak battery, a proper signal may/could still be generated, but your range will be greatly diminished.

Another reason the car may not respond to the fob could be interference from another electromagnetic source, such as your cell phone, a nearby TV, radio, or radar antenna, or high-voltage transmission lines.

The Owner's Manual devotes several pages to the Smart Key. Read up! You may learn something new like I did . . . I didn't know that the Smart Key System will disable itself if the system does not receive a signal from the key for more than 14 days, or, if the key is left outside of the car, but within effective communication range for more than 10 minutes.

By all means, CHANGE THE BATTERY! It probably is weak after 2.5 years . . . but rest assured, you will never be stranded because of a dead key battery. Use the mechanical key to open the door, then place the key fob in the slot to start the car.

 

I know I'm pretty late to the post (what's a decade?), but I've been arguing with both of the fobs for our '04 Prius. Changed both batteries, made sure accessory battery putting out appropriate power, made sure button under steering wheel in the right spot. Still nothing. Pressed the batteries further into the cavity and then hit a button and FINALLY got the red light on the fob. I ended up cutting 1/2" or so of toothpick and putting it on the back of the battery so the lid would push the battery far enough to function properly. Both fobs fixed.