A few people have expressed concern about the high-tech, expensive keys that come with the Prius.<br> The Sienna we bought 14 months ago came with exactly the same key arrangement: two Master keys (black),which work in every lock (and which are each attached to a "wireless remote control", or 'fob'), and one "Sub" key (gray) which opens every lock except the trunk. (Useful as a valet key.)<br><br> What we do is the following: my wife carries one black key with fob, since this car is primarily for her and the kids. I carry the gray key for the occasions when I need to use the Sienna. So I have to stick the key in a door to lock or unlock everything. Big deal. The other black key with fob we put away in a safe place. <br> <br> If she loses her keys, we'll dig out the spare with fob for her immediate use, and arrange to get a replacement. This strategy served us well last winter when her keys mysteriously disappeared for a month. The fact that I eventually found her keys in one of my coat pockets is beside the point - this arrangement is still valid and I recommend it for you two driver families. She will carry the gray key for the Prius, which is my commuting car. The gray keys are much less expensive to replace.<br>Sam

My suggestion to you is take the original "master" black key and keep it in a safe at the house. I work in the parts dept. at the local Toyota dealer and those vehicles that are equipped with an "Immobiliser" system (chip in key fob) need to use the factory original black master key to program new keys (up to 6 master and 3 sub/valet keys) to the system. The "immobilser" computer on Toyotas are integrated with the engine ECU (computer) so if you loose the original factory master key then you cannot program new keys into the system without buying a $1500 computer and about $300-$400 in other immobiliser accesories including a new key to get your car started....i have run into several customers at the dealership that have lost the original key and cannot make new keys to start their cars or in worst case they cant even start their cars....my suggestion...go to local dealership with original master key and spend the $50+ to make a new key and get it programmed and take the original and put it away for safe keeping....thanks<br>Jason

On Tuesday, September 26, 2000, at 09:35 PM,

&gt;&gt;You need a master key to program another key, but this is only useful if you have lost one of the other keys&lt;&lt;<br><br>How does the car know you've lost a key?<br>:-} <br><br>Seriously, does this mean that once you have had a fourth key cut, one of the originals no longer works? The car will only start if you use one of the last three keys used? I still don't understand the mechanism.

On Tuesday, September 26, 2000, at 11:53 PM,

At 8:07 PM -0400 2003/04/10,