Key Not Detected-Door not locking/unlocking correctly

Sounds like a dead battery in the key. Does it do it with both?

 

Does always this problem occur at the same place?
Then there could be interferences.
If not, ask your dealer to check the keys (both).

 

If you keep the FOB in your pocketbook, is there anything in there that can be interfering with it?

 

I do remember reading something in the manual about keeping your key and cell phone 3 feet apart, and iirc the reason was it will deplete your key battery faster. Not very realistic if both are in your purse. None of my purses are anywhere near 3 feet wide!

 

My smart key is pretty stupid. It is kind of moody, sometimes it works sometimes it does not... I’m trying to figure out if this is one more poor quality material to be included in my extensive list for the new Prius or if I'm doing something wrong with it...

The battery should not be depleted for anybody yet... I think it takes at least 1 year for it to deplete...

I'm avoiding carrying other electronic gadgets in my pocket with it, like cell phone, to see if it improves.

Also when the door handle is wet, forget about it.

 

I would think it's a battery issue in the FOB.

Sometimes we don't realize it but the buttons on the FOB can he pressed against and cause the fob to discharge faster. Happened in my prior car, so I found that out soon enough....

I do also know there is something about keeping the cell away from it, so I have not had ANY issue with the 2010 Prius...thus far.

Try your second FOB and if it works normally, it's the battery.

 

Like the oil change, I suspect it will vary widely among dealers... my dealer said I do have to take the key to them for battery replacement because a third party can ruin its programming… I'm thinking… BS or true?

 

There are several post in here relating to changing the battery in the fob. Very inexpensive. There does seem to be a trick to getting to the battery. Search fob or remote using the Google search function with priuschat.

 

The FOB battery? Don't you have instructions in the owner's manual to replace the Fob battery? Mine does.

 

If a 2010 fob is similar to a 2008, it's a simple fix. I've done it on my 2008. There are some good detailed instructions on this site.

You will want to have an eyeglass screwdriver kit (they're cheap). The screws are tiny. Good luck.

 

It's a "disk" or "coin" battery - size CR1632.

I think it's a common watch battery and available any place where watch batteries are sold.

It's inexpensive -- about $3. Amazon sells one for $2.75 each (and you can buy them for less than that if you buy a multi-pack):

http://www.amazon.com/Energizer-Lithium-Watch-Battery-CR1632/dp/B001D0E21Y


You install it with the positive/+ side facing up.

 

I'm thinking it is BS. I replaced the batteries myself in both my 2001 Prius and 2004 Prius. It was a $1.89 battery, IIRC. The batteries lasted 4-5 years or more. Very easy to do...takes about 2 minutes.

However, I just popped open my 2010 FOB. Pull out the mechanical key and you can use the end of it to twist open the case. But once it is open it IS different. No battery to be seen. It looks like you have to remove the tiny circuit board from the clips in order to get to the battery.

Has anyone done this yet?

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Back to the original post. I carry my phone and FOB within 1-12 inches all the time. Never a problem and very long FOB battery life. I'm 99% sure that this is a myth. The only interaction that I see as likely is that the metal of the cell phone can block the RFID interrogation signal so that the key FOB is not seen.

All that said I did experience one FOB failure like the original post a few weeks ago. I just filled up with gas and went to start the car (FOB in pocket like every day). No key detected. A couple of more attempts and I got the message to put the key next to the POWER ON button. No luck. After 2 more tries it started like normal and never happened again. Cell phone was in cupholder.

3PriusMike

 

Owner's Manual pages 460 and 461 gives you a complete description for replacing the 2010 key fob battery along with replacement battery number.

 

To change batteries on Smart Key. Pick up fob, remove the mechanical key. Once mechanical key is removed insert flat metal end into slot (note slot is located next to the slot for mechanical) twist. The cover to the key fob seperates. Gentlely lift the circuit board from key fob. Remove battery, insert new battery (battery is avaliable at Radio Shack, Walmart, Target and just about most grocery stores). Reverse procedure to reassemble key fob.

 

Isn't the MID supposed to give us a warning light when the battery in the key fob is low charge?

 

There are a lot of cautions out there about cell phones and other electronic equipent that transmitts. Some of these warnings are left over from a few years ago before the electronics improved to allow lower power transmitters. I don't know the frequency that the smart key uses but it could be possible if the system uses a rolling code that a cell could cause the smart key system not to reconize yor key for a short period of time. You may also notice a lightning strike near by will confuse the system.

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