[Smokinjoe73]

So I just bought a sweet new to me 2010 yellow 251(!!!!!!!iiiiii)
I have only one key with it so my question is, do I need the electronics in the key for it to run? Meaning if I have a key cut to work but it doesn't have the chip in it will the car run?
Also, can I transfer the electronics from a key from my old 251 to this one somehow?

Lastly, if no to transferring or using without chip where is my best source for a replacement key?

Thanks for any help

Will this work?

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[vadsoom]

There is a transponder in the key that is “mated” to the immobilizer circuit in the car. You can probably have a new key blank cut for your old 451 key fob, then have the car reprogrammed to accept your old key fob. The dealer can do this (yuck) or a locksmith with good skills and the correct equipment can do this in minutes. It’s not always inexpensive, I think I paid $50 for cutting the blank and programming, but it’s far less than the dealer will charge!

 

[gtdump]

I would like to add that, on the 451 at least, when you have new keys added to the Smart they must all be present and added one at a time, any left out will no longer work.

 

[dhlairbusb4]

S, my understanding is these keys are vehicle specific, that is they are married to the vehicle ECU and SAM. Using a key fob from another car, with a new key blade, may unlock the car manually, and turn the ignition, but most likely will give you a key symbol, and not start the car.

 

[twcom]

Google ( ilocksmiths Brooklyn NY) ask for a quote for smart car key. Also look for a YouTube video by them

 

[whtlightning]

I was in the same situation. I bought a 2014 ED and only got one key. I checked with MB and they wanted $450 to furnish, cut, and program. That wouldn't do so I started looking for a locksmith. I bought a new key fob off of Amazon for $24. It took several weeks to find a locksmith in the DFW area that would even acknowledge me after I told them it was a Smart. Finally found a guy who drove out from Ft. Worth to Decatur, cut, and programmed my keys for $40. All is well now, but not without a ridiculous amount of effort. Good luck.

 

[Smokinjoe73]

This is harder than I expected or at least more expensive. ilocksmiths charges $110 even if I have my own key to cut & program. Gonna keep shopping.
Isnt tech advancement great? Keys that cost a fortune. I miss the old days.

 

[johngowms]

This is harder than I expected or at least more expensive. ilocksmiths charges $110 even if I have my own key to cut & program. Gonna keep shopping.
Isnt tech advancement great? Keys that cost a fortune. I miss the old days.

This is harder than I expected or at least more expensive. ilocksmiths charges $110 even if I have my own key to cut & program. Gonna keep shopping.
Isnt tech advancement great? Keys that cost a fortune. I miss the old days.

I have an key that is not fobed. I can use it to unlock the door and to start the car and drive. However, I can not lock the car with it and when I use it to unlock the car the alarm goes off until I insert it in the ignition. Are y'all saying there is a chip in it somewhere that the car recognizes? I think not, as there is no way to open it to replace a battery.

 

[dhlairbusb4]

Show us a picture if you can.... the normal key fob is circular in shape, and has the chicken head emblem on one side, and four buttons on the other, lock, unlock, cabrio open, and alarm. I think the hard top models have a button for the hatch.

 

[whtlightning]

I had my best luck using Facebook Marketplace. Ours is full of ads advertising replacement keys and programming. 99% of the folks I contacted either ignored me, replied they could not make a key for the Smart, or were horrendously expensive to come to Decatur. Since I have an electric, a 40 mile trip to Ft. Worth and back were not an option. As I said, I kept at it and finally found a guy with the correct equipment that was willing to make the trip at a reasonable price. Keep at it, you'll finally find someone.

 

[twcom]

I have an key that is not fobed. I can use it to unlock the door and to start the car and drive. However, I can not lock the car with it and when I use it to unlock the car the alarm goes off until I insert it in the ignition. Are y'all saying there is a chip in it somewhere that the car recognizes? I think not, as there is no way to open it to replace a battery.

ok now this is different. What type of Smart do you have. You are opening starting and driving off in the car with a cut key but no key fob ? and a second key with a key fob is not in the car. Is that what you are saying

 

[dhlairbusb4]

Inquiring minds want to know!!!

 

[vadsoom]

I have a copy of the 451 factory service manual and can confirm there is a transponder receiving antenna mounted just under the ignition key slot. Just below the ignition tumbler assembly is the immobilizer circuit enclosure.

The hardware is there, but I have no way of knowing whether the SAM is “listening” to the immobilizer circuitry. Your observations have prompted me to actually try my 2008 without the fob.

 

[dhlairbusb4]

It probably will not start with out it.

 

[gtdump]

It probably will not start with out it.

That is my expectation, but I have been surprised before.

 

[dhlairbusb4]

I hope you are... it would be quite a surprise to all of us.
I have a spare key that worked for a while, then stopped... then started again, then stopped again.
I plan to send it in to SOS diagnostics when time permits.... but I have to send both keys, the SAM, and ECU.

 

[toaster]

I have an key that is not fobed. I can use it to unlock the door and to start the car and drive. However, I can not lock the car with it and when I use it to unlock the car the alarm goes off until I insert it in the ignition. Are y'all saying there is a chip in it somewhere that the car recognizes? I think not, as there is no way to open it to replace a battery.

Likely the key you have is a cloned one. The battery in the OEM smart key is only necessary to lock/unlock the doors remotely.

When the key is inserted into the ignition, a transponder coil is used to query the key for the correct code.

~toaster

 

[johngowms]

Likely the key you have is a cloned one. The battery in the OEM smart key is only necessary to lock/unlock the doors remotely.

When the key is inserted into the ignition, a transponder coil is used to query the key for the correct code.

~toaster

I does appear that the shell could be in two part, though there is no way to open it. The key in question on one side has some markings and Italy stamped on it in the middle and again near the metal bottom is the word Italy. the reverse side Has " TK100 " stamped in the middle and near the base of the plastic

Likely the key you have is a cloned one. The battery in the OEM smart key is only necessary to lock/unlock the doors remotely.

When the key is inserted into the ignition, a transponder coil is used to query the key for the correct code.

~toaster

Aha, thank you, toaster. My extra key looks as if the plastic case is in two parts that I cannot get into. in the middle of the plastic on one side it has some markings and the word "Italy" and "Italy is in very small letters at the base of the plastic. The other side has "TK100" in the middle and "PG33U" on the base. So, I have a cloned electronic key for my spare. My computer hiccuped during my first response, that is the reason for the redundancy of this response.

 

[toaster]

I does appear that the shell could be in two part, though there is no way to open it. The key in question on one side has some markings and Italy stamped on it in the middle and again near the metal bottom is the word Italy. the reverse side Has " TK100 " stamped in the middle and near the base of the plastic

Aha, thank you, toaster. My extra key looks as if the plastic case is in two parts that I cannot get into. in the middle of the plastic on one side it has some markings and the word "Italy" and "Italy is in very small letters at the base of the plastic. The other side has "TK100" in the middle and "PG33U" on the base. So, I have a cloned electronic key for my spare. My computer hiccuped during my first response, that is the reason for the redundancy of this response.

Definitively a clone.

Keyline TK100 Universal Electronic Head

Keyline TK100 Universal Electronic Head Keyline USA Our Automotive Brands

www.internationalkeysupply.com

~toaster

 

[dhlairbusb4]

The one on the left looks like a smart key, and can be opened with a coin, or screw driver... when it opens its easy to replace battery, check contacts etc...