2002 Prius lost all Master keys

Second method works fine. Whether you program a key as master or sub is also independent of whether the key is mechanically cut as normal or valet, so if your own key that fits happens to be the valet cut, you can program the car to recognize it as a master if you want.

For the parts of the door/key dance that require the eBay key, wrap foil around your own key's transponder head and use it in the lock cylinder while the eBay key sits somewhere in transponder range. For the parts that use the key being programmed, move the eBay key out of range and take the foil off your own key.

-Chap

P.S.

For anybody who has both their master and valet keys, I would love to see comparative photos showing the difference in cut. I only got master keys with my car and I'd really like to know how to cut a key that won't open the trunk.

If you're worried about somebody copying your key from the photo, you could take comparative photos, identify the part of the cut that's different, and use GIMP or photoshop to blur the rest....

 

I bought a key on ebay and had Walmart cut the key for FREE and programmed it myself from directions online. No problems.
TomK

 

Hi Tom,

Did you do that without having any working master key to start with? I think that's what the OP was getting at.

-Chap

 

Nope, I had a working master that was bent and cracked but worried me.
I should have clarified that I was giving information AFTER he gets his valey key to work somehow what he could do to move forward.
Just thinking, maybe a better question would have been HOW and WHY did he end up with the car with only a valey key?
TomK

 

Eh, I ended up with a car with two masters and no valet. Previous owners don't keep everything, and they might not always know the difference.

His valet key probably works fine right now for driving the car. The catch is that, as a valet key, it is normally programmed as a sub key in the immobilizer, which means it can't be used for the programming of additional keys, as you were able to do because you had a master.

The OP officially needs an immobilizer change, or to look into whether an immobilizer reflash/reset service is available for Gen 1 (which may well be equal effort to just replacing the thing, and possibly no cheaper if there's one on eBay for $150).

Hmm ... I don't know whether immobilizer reset is a feature accessible in the professional/locksmith version of Techstream, and I definitely don't know whether it's in the pirate Techstream versions being sold with MiniVCIs. I sort of hope not, but that rarely stops anybody.

-Chap

 

There are locksmiths who can do an immobilizer reset. They basically copy the memory of a new immobilizer into yours. Expensive, but a lot less that replacing the entire unit.

 

I'm piggybacking onto this discussion. I just bought a pair of uncut 4C keys from eBay that are en route, however I didn't read all the fine print. The listing is claiming that onboard programming doesn't work for these keys with the Gen 1 Prius and to take them to a locksmith/dealer. Any reason these particular keys wouldn't work, or do you think the seller just isn't familiar with the onboard programming process? Thanks.

 

Yeah, I'm good on the key type (no dimple), and I have a master key. I don't think it's going to be a problem regardless of what the listing said.

 

Please allow me to clarify what is going on with chips and programming procedures on Prius:

1. 2000-2003 Keys can be added, if you currently have a master key. A master is one that will produce NO flashing of the immobilizer light when introduced to the ignition by either turning a key or passing a swipe, depending on two your model is so equipped. A valet key will illuminate the theft light for about a half to three quarters of a second, then extinguish. Valet keys can not be use to initiate adding keys. If all keys are lost, the system can be reset, but it requires removal of the ECU to service. Once done, you will have master keys once again. This is far less expensive than replacing the ECU or trusting EBAY as your solution to all things cheap.

Alternatives include copying and cloning the Valet key.... beware of cheap clone keys at hardware stores... they fall apart ( snap together design is weak ) and they do not use a quality read/write chip. They use an emulator that is not close to as reliable as the proper RFID chip found in original keys. a JMA TPX chip is somewhere in between these cheap clone keys and an RFID chip.... those are the ones we use, if cloning is the only solution the client will tolerate. We cut the key blade to code as well, something the hardware store can not do.

2. 2004+ Now things are easier.... on cars 2004 an newer, we use a scan tool to do programming, immobilizer reset and other functions via OBDII port.

Beware of cheap DIY diagnostic tools, dongles, devices that are being dumped online. Some work, some do not... many are pirated technology that is so old, you will trip off the dash like a Christmas tree...requiring someone like me with a LEGITIMATE scan tool to reset and get things working right. One can roll the dice to satisfy a desire to find a cheap solution, but it is very risky, can be very expensive, and it is supporting theft of technology, albeit OUT OF DATE technology. My scan tools are updated monthly. Little improvements and fixes are alway being added to deal with and overcome artifacts found in cars over the years, as well as to deal with FIRMWARE UPDATES found in vehicles.

 

Plan C is to acquire a previously-enjoyed immobilizer on ebay, and then send THAT immobilizer to any of the 3 or 4 ebay-listed locksmiths that show up when you do an ebay search for "Toyota reflash". Provide the necessary information, plus $, to the locksmith, and a week later you can have an immobilizer plus a number of working master keys for your car. Replase the immobilizer ECU in your vehicle, test, and you are set. Total cost is half (or less) that of purchase of a blank immobilizer plus keyset from Toyota.

Necessary information to the locksmith is stuff like VIN, evidence of registration, and evidence that you are who you are (usually a driver's license), plus the mechanical key cut code.

The advantage to this system is IF the reflash is unsuccessful, you can restore the original immobilizer ECU to the car, and you can still drive it whilst the replacement issue gets sorted out.

The tricky bit is to find your mechanical key cut code, which is supposed to be somewhere inside the door on or around the lock mechanism, OR you can bring your registration and license and VIN to a Toyota dealer and they can look up the key code for you.

 

Just so nobody reading this runs into terminology confusion, for Gen 1 there are two terms in play here, "sub key" and "valet key". The "valet" term only refers to the shape of the cuts in the metal key: a valet key will start the car, but not open the trunk.

The "sub" term only refers to the registration of the key to the car: a sub key will light the theft light for a moment, then extinguish, and a sub key can't be used to register other keys.

They're confusable but different things: when new, the car came with two black keys and a gray one, and the gray one was both cut as a valet and registered as a sub. But you can register any key whichever way you want; you could re-register the gray one so it could also be used to register keys, or you could re-register one of the black ones as a sub so it couldn't. (Doing that to both of your black ones would suggest a lack of foresight, though....)

-Chap

 

If anyone loses all keys on Gen1, I usually have Gen1 Immobilizer modules with matching master key and ignition cylinder sets for sale. Current price $160 delivered. Install parts yourself then car will drive.

 

still available? I’m putt 2 gen 1’s together butcannot overcome the immobilized despite changing all the correct hardware

 

Switched all pertinent hardware from a my 2001 (blown engine) to 2003 but immobilizer still engaged(?!). I don’t understand why. Will this fix it?