So I just bought some new keys (just the shells) and transferred all of the guts from my old keys (transponder + remote) into those. This morning, starting the car is nearly impossible.
It will keep turning over but won't start 95% of the time. Granted it's a little cold but this has never happened to me before, so is it safe to say it's the immobilizer?

If so, what did I do wrong? I tried pulling one of the chips out and putting it back in the key upside down (curved side up), but that didn't seem to solve the problem.

NOTE: I Don't have the new keys cut yet, so I have to use the old gutless key to start the car, and hold the new key (w/ transponder) up to the ignition. It should still work, though, right?

_____

 

Yes, that method of holding the transponder close to the ignition should still work.

 

It will attempt to turn over with just the key. But the ECU will not allow the car to start unless the chip is working and in the proper location.

 

So I took everything to the dealer. They said they "reprogrammed" one of the keys and it worked fine after that. Charged me about $100. I don't know how it got UNprogrammed between removing the guts from the old keys, and putting them in the new ones, but I guess they did. A warning there.

And now because Home Depot mis-cut one of the keys I'm gonna have to do the whole thing over again for the 2nd key.

So, new question, I'm I going to unprogram it again but transplanting everything into a new key shell? I'm still unclear on what happened.

 

the dealer didnt reprogram your transponder, they just took your $100. mine was acting up until i flipped the transponder. before you put the cover on, make sure the car will start.

 

Clearly, thats why his car worked fine after he went there. They simply took his money, and a miracle happened that his car works fine now.

 

yeah i lost my key also and dealer wanted to charge me 200+ for it, i went to a local key maker and got it done for 60.... but its also without the lock and unlock button.

 

It is easy to program the keys too. do a search on here and you will find it. DIY and save money.

 

I know this thread is a bit old but I was having this exact same problem after replacing the guts. I did a little more reading though and found that the immobilizer transponder is actually an RFID inside the key and if you are replacing a key with lock and unlock buttons this RFID is fairly easy to take out and move over to the replacement saving you the $100 that the stealership will charge you.

I have attached a picture of where the chip is located in the original key. To get the chip out I used a flat head screw driver and a hammer and chiseled around the edge until I got it loose. It is encased in some kind of adhesive though so dont be surprised if the thing is bit difficult to get out. Once out just place this in the vacant slot in the new shell you just bought and go try to restart your car. Took me about 15 minutes and saved me the $100 the dealership wanted

 

THANK YOU!

I just replaced my key and noticed that the car wasn't starting... started messing around with the fob and noticed that when the old (original) fob was next to the key, the car would start without issue.

I'm gunna go dig this out and put it in the new keyfob encasing.

Really appreciate the help .

 

Spare Key -Car Won't Start but unlocks the driver Door and locks the driver door something the original key won't do? I lost my original key at work. But this key doesn't have any buttons just looks like a valet key but doesn't even lock the glove box? So can someone help me understand

my dad cut the key himself at our work. But the car won't turn over with the Spare Key he made. But does everything else except start the car. If anyone lives in South Carolina and can help me with this issue please let me know. I own a 2005 Scion tC if that helps with anything.

___