Key fob stopped working

welcome!

you're supposed to recycle lithium batteries

does the red light light up when you press a button?

how is the 12v health?

do you have a second fob?

 

I’ve a 2009 Prius
The lock and unlock functions of my fob stopped working a couple of days ago. I replaced the battery in the fob and that did not solve the problem. I have tried with the Key button under the steering wheel in both positions.

The button must be in the "out" position for the SKS system to work

I’m thinking now that the battery in the fob might have been still okay because I could always start the car with the fob in my pocket.

Possibly.

I didn’t have to hold it up to the power button.

I don't understand this. A 2009 in NC should be a Gen 2, which has a FOB slot so the car can detect the RFID chip in the FOB. If you have no slot then is the car actually a 2009 Gen 2?

As mentioned before, does the red light energize when you press a button?

Here's another way to check FOB communication with the car, not many people are aware of this...

It's easiest to do at night, or just hold the FOB in a shadow.

1. The FOB and car will auto detect each other when you approach the car and are somewhere between the side mirror and the rear tire on either side of the car. Walk toward your car with the FOB in your hand. Once you get close to the car (in the autodetect area), you'll see the red light flash once your're in range and the interior lights will turn on. Do not open the door, the FOB red light will continue to flash about every 4 seconds. The light will turn itself off after about 20-30 seconds, and the FOB will continue flashing about every 4 seconds.
2. Touch the door handle and if locked, it should unlock.
3. Open the door and sit in the seat. No feet on pedals. Look at the FOB again, the red light should now flash about every 7 seconds. It will flash like this about 5 times and then stop.
4. Foot on brake and press the power button. The red light will immediately flash when you press the button and as long as communication and permissives are good, the car will power up. The FOB will no longer flash until you turn the car off.

 

Do you have another spare FOB ?
If not, you should get one.

The most obvious answer is: Check the new battery to be SURE that it is installed right AND that the new battery is good.
Most locksmith shops can help with this these days.........at a cost MUCH less than a dealer.

 

Find a picture of a 2004-2009 and a picture of a 2010-2015. Both the front and rear are very different.
But if you have an sks button, it’s a gen two.
There is a red light on the fob. If it doesn’t light up when you push a button, either the battery is in backward, or it’s dead, or the fob died.
If you’re gonna diy, you need a meter

 

Here's a photo of a Gen 2 key fob and a 2010 key fob. Which one matches your fob? And the little black hole near the corner is actually the LED we are talking about.

 

was it imported?

 

This doesn't prove the battery is ok, as the car will start with the key in the slot, even if there is no battery installed. However, the car starting with the key in your pocket does prove the battery is working.

The LED is inside and shines through the hole in the case as illustrated below.



If your case doesn't have this hole, then it is most likely not an OEM case, but a poor knock-off. As long as it works, that is the main thing.

 

An aftermarket FOB case then? I recently got two of these from Amazon and the quality is definitely suspect compared to OEM. I had to return the first one because the key blank would not lock into place (metal tab was weak). These have the LED hole.

If you still have a fully functioning FOB, use it to (re)pair the other one via the "chicken dance". No costs other than your time. If that doesn't work, I'd try swapping out the internals to a new FOB case and pair again.

GOOD LUCK!

 

Rut-rho Reggie.

Time to consider a professional locksmith ($$) or Toyota dealer ($$$) but I would swap out the guts (including the tiny RF chip!) into a new FOB case (about $12) first.

GOOD LUCK!

 

This is going to sound utterly unbelievable to a lot of folks. I would not have believed it if I hadn’t experienced it firsthand.

I’m on a 2,300-mile road trip across the country. I was caravanning with my housemate, and we got a couple of walkie-talkies just for fun. I made sure my Prius was road-trip ready at a Toyota dealership; to have less chance of issues. She’s all good! The first two days of the trip went great. I did some repacking in New Mexico before heading to Colorado; here, I made a critical mistake that would frustrate me for a solid 12 hours. While repacking, I realized that the charging cradle of the walkie-talkie fits perfectly into the center console and then could be plugged into the “cigarette lighter” charging port. Hey, I’m old enough that this is its name. When I arrived in Colorado and parked at the hotel, I couldn’t lock the car with the fob, and it kept beeping at me while it was off and the door was open. I was bewildered and tired, so I slept on it and started researching the issue on the internet (finding this thread) and calling locksmiths and finally the local dealership. The locksmiths and dealership were utterly perplexed, and each offered to investigate it for a price. I decided to dig in a bit more myself. While reading through the manual, I noted several “caution” blocks talked about keyless entry signal interference from various devices (airports, other fobs, large displays, etc.).
I had my housemate's spare fob in the car, so I tried removing it from the center console; no luck. Then I asked myself what changed from working to now. The only radiofrequency change I could think of was plugging in the walkie charger, but that couldn’t be it…right? Wrong! I unplugged the walkie charger from the vehicle and closed the driver's door, and the fob worked like a champ again. So, I plugged it back in, and it failed again. Of course, I unplugged it, and it worked again. I had to know for sure that it was the cause and not just a fluke.

If you’re having a similar issue, think about what tech you might have introduced into your vehicle recently and try removing it. In this day and age, everything transmits or receives some kind of signal. It’s more and more likely for these things to get in each other’s way, in my opinion. I hope this helps some of y’all or at least gives you a laugh.

- Gio