My experience in getting a replacement FOB

The fob and the car both use rolling encrypted codes. I believe it is 128bit at minimum with a 8bit counter for synchronization. Every time you press your button on the fob both the car and the fob change to a new random 128bit value. With multiple fobs, all fobs must be used at least once every 255 (2^8) key presses. Otherwise they will go out of sync.

"Programming" is just learning them to eachother and resynchronizing.

It is the full Toyota TechStream program. Anyone can purchase it with the money. Counterfeit programs are available too. Cost is between $1500 to $3000 for the program. Additionally, if you want to do key fob programming, you must have a Toyota subscription which bumps the costs up significantly per month, or you can buy outright for something close to $6000. This outright buy may have changed, it has been a while since I researched it.

It is a timed sequence that is highly unlikely to happen with normal use of the vehicle. It wouldn't be very fun if all it took was opening the door twice. Every time you did that you would kill the car. The "chicken dance" is there for a reason.

Sounds right. I have heard 5 or 6.

The used fob definitely can be programmed to be accepted. He did not do the procedure correctly or he does not have a techstream license that allows him to resync fobs. It wouldn't be very fun if you could buy a $1500 program, a $100 key from ebay and steal any $20k to $30k Prius you want...

You made a contract with the locksmith who failed, but you get what you pay for. The ebay contract I am surprised you are getting a refund. You should have known this or take it as a lesson. You can still take the fob to a legitimate Toyota dealer with a full subscription (not all have them because they are expensive to maintain) and have the used fob be accepted. It is a 2-3 hour labour charge depending on the dealer. The local dealership charges $85/hr.

 

Did you hear what 2k1toaster saud?
"...take the FOB to a legitimate Toyota dealer."

 

This sounds like allot of rigmarole. There was another member who lost his fob that was hooked by the key loop on his belt while he was out of town - any one's worst nightmare. He had to have his car towed home.

I purchased key fob insurance for $95 at the time of sale wondering if it was worth it. Now after hearing about these incidents - I think it was justified. I've heard buy a replacement fob(s) from the dealer can run as high as $500 including reprogramming. Ouch!

 

does the need to use both fobs at least every 250 times include the gen II? i have never used my second fob and wonder if it will work if i need it.

 

"With multiple fobs, all fobs must be used at least once every 255 (2^8) key presses. Otherwise they will go out of sync."

I dont know if I am reading this right. But I have a 2010 and it came with two FOBs. I have been using one for two years. The other is pinned to my cork board in the kitchen and has never been used and the battery was taken out so it wouldnt deteriorate and create a problem.

I just put a battery in the 2nd unused FOB and it works fine.

So could someone please elaborate on how the FOB goes out of sync?

Thanks!

 

Anyone?

From my observation the FOB does not use a rolling code since my two year old (previously) unused FOB works fine.

 

When a fob goes out of sync it will not work, but most likely you won't know it. Wireless security protocols have an automatic way of resynchronizing. Generally it involves having to try a second time. Most of us will just go "Huh, that was weird" and go on with our day, never realizing that the fob resynchronized.

Tom

 

Thanks!

 

-----an automatic way of resynchronizing. Generally it involves having to try a second time.-------

So I don't need to dig out my unused spare fob every 3 months? I have not read yet of a member having a fob that went out of sync. For what its worth , when I went to a the local Toyota dealership to program a spare fob, I was told they do not go out of sync (2004 model).

 

Exactly. You don't have to dig out that spare fob.

Tom

 

I have bought 2 different FOBs on ebay and took them both to 2 different toyota dealers who both told me that they can't program them. The first one they said it may be the FOB, when I brought in the second one they told me they could not be reprogramed, and that I had to buy a new one.
I need a second FOB. Can a toyota dealer program a used FOB to my 2010 Prius? or do I have to buy a new one from Toyota.
Thanks

 

The process for adding a used FOB is to follow the same procedure as is used when all keys are lost. Once the "Smart Key Reset" is complete, add the used FOB first, and then the other FOBs. Since you still have valid keys, it is not necessary to do the reset with the car OFF. The reset takes about 16 minutes, so figure 1/2 to 1 hour charge for the whole process. Anything more is pure profit.

 

My understanding is that you need to find a way to remove the stored VID from the used smart key fob in order for it to be programmed to the vehicle. Has this changed for the Gen III?

 

Once the VID is burned into the key, it cannot be altered. You program the car's module.

One clear way it was explained; think of the VID as cutting a physical key - you cannot 'un-cut' it once it has been cut.

 

Since it is possible to use eBay keyfobs, this can't be the whole story. In particular, I recently programmed a used Prius Gen3 keyfob for a Lexus CT200h. Apparently the VID is set in the first keyfob programmed after a seed reset. So to add 2 used keyfobs, you have to do 2 resets. After doing a seed reset, the car has lost track of all keyfobs and they have to be added back in with the normal add-key procedure.

So there are two elements involved in adding a used keyfob to the car. The first is to set the VID in the keyfob, and the second is to register the keyfob ID in the car. The seed reset is an available way to get a VID stored in a used keyfob.

As for the Prius keyfob for the CT200h, they both use the same circuit board in the keyfob case. The cases are different, as are the mechanical keys. I haven't found a locksmith willing to even attempt cutting the Lexus key pattern on a Prius blank. One even accused me of wanting to do something illegal when I asked! I currently have a Toyota Crown key blank on order that looks like it will fit both the lock and the Prius keyfob case.

 

I am not a locksmith, nor do I have Level 3 access to TS. I am just an enthusiast, and capable person.

The best references I have found on fob programming, all assert that that the VID is programmed *once* onto a *new* key. It is essentially "flashing" the circuit, burning in the VID. Once this is done, you cannot *re-burn* a new VID; it is a one-time operation. If the physical key cutting analogy doesn't make sense, then think of it as a write once CD.

My perception tells me if this is the case, then how is one able to get a vehicle specific key to operate on another vehicle? It obviously can and has been done. The answer must be that the module can be programmed to accept the non-concurring VID.

How is this done? Using TS, non-OEM locksmithing programs (found on the web), or turn-key systems.

So we have a key with a non-rewritable VID, asking for access to the SKS module, which dutifully declines to operate the vehicle. We use a program to access the module, delete the stored VIDs, prove legitimacy, and re-enter the new (pre-existing and non-matching) VIDs.

What appears to be the case, is if one has an OEM key with correct and matching VID, then a reset using TS essentially proves the programmer as being legit, and non-matching VID fobs may be entered; eg. no re-seeding is required.

If, on the other hand, no correct VID fob is present, then legitimacy is questioned, and a re-seed is required.

There is *so* much misinformation out on the web, that finding hard-core truth is difficult. I have yet to find anything that I can point to that is clear and decisive. All I have been able to do, in an enthusiast's and home mechanic's sense, is read everything written, and try to pick out what seems creditable, based upon some use of logic.

If one is interested and has read what is out there, then the allegations of *impossible*, *only with re-seed*, *replace the ECU*, and *rolling codes* all have been misinformation.

Personally, I would love to know the truth, not because I am a thief, but because I am an owner.

If I am wrong in what I write, then I would like to be pointed to an information source so I could become better educated and see where my fact finding has gone astray.

This is an elusive topic, perhaps a good thing, since it deals with the security of our vehicles. Unfortunately, it appears if one is inclined, there are already back-doors available, not utilizing a OEM level 3 seed. I am not divulging more

Addendum: I think the seed re-set might equate to filling-in for a correct VID key (original, or new duplicate flashed from an original) in the absence of one. I am inclined to believe that re-programming needs a form of authorization, a correct, matching VID fob, or a re-seed.

 

I recently purchased used 2010 Prius with only one smart key in Los Angeles area. For spare, I bought new fob with blank key on Ebay for $66 bid. Longo Toyota in El Monte programmed the remote for $90, including cutting the key. They cut it at their Lexus dealership next door. All the other Toyota dealers I called were asking a minimum of $125 plus additional charge for cutting the key, which they have to send out. To program smart keys, I recommend contacting Toyota dealer that also has Lexus dealership.