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Great! Thanks! So that's a solution IF you don't mind sacrificing security to save $280 on a spare transponder key:

If you only have 1 transponder key, to avoid frying your BCM if you lose that one, glue it inside the steering column cover & use cheap non-transponder keys to lock, unlock & drive.
 

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A Fiat with the alarm activated and no valid key will melt the BCM, permanently disabling the car. The car will have to be towed, the BCM replaced, and new keys precoded and programmed to the new BCM.
Hold on! So if I'm in the grocery store & someone breaks my window to steal a laptop or something, & they open the door to grab it, my car is immobilized & I'm stranded with around $1,000 damage?! (towing + two $280/keys + BCM + window)

if you unlock twice, it doesn't set off the alarm.
I just tried that with one of my 2 functioning transponder keys on my 2013e with all software updates & it set off the alarm & wouldn't shut off without the push-button:

  • I tried unlocking twice before opening the door & the alarm activated.
  • I tried unlocking 3 times before opening & the alarm activated.
  • I tried unlocking, opening, unlocking.
  • I tried unlocking, locking, unlocking, opening.
 

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Thanks.

1) I meant get a cheap non-transponder copy made just in case, so that after loosing your only transponder, you could open the door with the copy, alarm sounds, pop hood, disconnect 12V. Still possible BCM destruction?
Did some digging. Once the alarm is activated in the BCM, not even removing power will reset it. So it's melted if there are no authorized keys available.

ga2500ev
 

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Hold on! So if I'm in the grocery store & someone breaks my window to steal a laptop or something, & they open the door to grab it, my car is immobilized & I'm stranded with around $1,000 damage?! (towing + two $280/keys + BCM + window)
Only if you have no authorized transponder keys. As long as you are not in what is called the "all keys lost" situation, you can always deactivate the alarm with either the remote button or by turning an authorized key in the ignition.

It's losing all authorized transponder keys that's the danger zone. And it's real danger if the alarm is activated in that circumstance.

As for deactivating the alarm from the door...
I just tried that with one of my 2 functioning transponder keys on my 2013e with all software updates & it set off the alarm & wouldn't shut off without the push-button:

  • I tried unlocking twice before opening the door & the alarm activated.
  • I tried unlocking 3 times before opening & the alarm activated.
  • I tried unlocking, opening, unlocking.
  • I tried unlocking, locking, unlocking, opening.
From my digging around, it looks like the magic incantation is to unlock the car with the non transponder key, then hold the key in the door in the unlock position for 10-20 seconds. Supposedly this is supposed to roll the windows down. It's also supposed to deactivate the alarm. Let me go test it (BRB)...

No Bueno. I held it for 60 seconds. No window movement. Alarm fired off immediately when the door opened.

ga2500ev
 

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I agree, 280 Sounds pretty good, the dealer near me in Glendale is asking 400!!?
$280 isn't terrible for a replacement key. It's expensive, but you don't have a lot of options. A locksmith can only cut the physical key but they can't program the transponder.
 

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Just for the record, there certainly are locksmiths who are equipped to program transponders. It's on you to get the right fob with the correct FCC ID and chipset, but I'd say most locksmiths these days are set up to do the programming waaay cheaper than a dealership.
 

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Just for the record, there certainly are locksmiths who are equipped to program transponders. It's on you to get the right fob with the correct FCC ID and chipset, but I'd say most locksmiths these days are set up to do the programming waaay cheaper than a dealership.
When I was working through this problem, I called over 5 locksmiths. None of them had the equipment to precode and introduce new keys. I believe I have a post in this thread that describes the entire process.

ga2500ev
 

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2017 Fiat 500e (Billet Argento), 2015 VW Golf Sportwagen TSI 5MT (Tungsten Silver), 2002 Honda VFR
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One way to cheat is remove the chip from any remaining key and glue it close to the transponder reader inside the plastic shroud then from here on out you can use any abundant aftermarket keys non chipped or whatever to your liking. Only down side is obviously it’s easier to circumvent your cars security features but the way I look at it, if they want it bad enough they’ll take it anyway.
 

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One way to cheat is remove the chip from any remaining key and glue it close to the transponder reader inside the plastic shroud then from here on out you can use any abundant aftermarket keys non chipped or whatever to your liking. Only down side is obviously it’s easier to circumvent your cars security features but the way I look at it, if they want it bad enough they’ll take it anyway.
I broke my one and only key exploring this route. I made the mistake of thinking that the antenna was the transponder. Separating the two breaks the system. I was able to get some help transferring the chip from the broken board to an intact one fortunately.

My advice is to not remove anything and place the entire board in the steering column. The battery is unnecessary as it powers only the remote fob parts of the key. It is by far the cheapest way to get multiple keys for a 500e. However, the concerns are the loss of any remote functionality, and the above mentioned losses in security.

ga2500ev
 

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Can you explain why loss of remote functions? I’ve done this with a Nissan Sentra of the past and remote programming still works just disable the transponder part of it.
 

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Can you explain why loss of remote functions? I’ve done this with a Nissan Sentra of the past and remote programming still works just disable the transponder part of it.
You have a single authorized fob which is disassembled and embedded into the steering column. So that fob is no longer accessible outside the car, right?

The transponder and remote functions are embedded into a single chip on an integrated board in the fob. Here's a picture of the board:
108592

The chip on the right hand side in the middle of the board on the left is the integrated transponder/encode/remote chip. The wire bundle at the top of the board on the right is the antenna for the transponder. Without a battery, this unit can still be read by the reader ring surrounding the ignition, but remote functionality is disabled.

So essentially this entire board would need to be inserted into the steering column. Both the lack of accessibility and the lack of battery power effectively disables the use of this fob for remote functions once it's put into the steering column.

ga2500ev
 

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Yea but isn’t the transponder and remote keyless still separate systems, meaning you can program another remote to the car but just not the transponder portion of it. At least that’s how it is with Nissan and Toyota vehicle’s I’ve worked on like a consumer can easily program the keyless remote themselves but not the transponder portion even if the key is all in one design like ours. All I’m saying is if I embed the transponder I should be able to purchase couple of aftermarket keys that don’t have the transponder but has the remote fob electronics and should still be able to lock and unlock with a second remote. Not sure how fiat differs then all other makes in that regard.
 

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Yea but isn’t the transponder and remote keyless still separate systems, meaning you can program another remote to the car but just not the transponder portion of it. At least that’s how it is with Nissan and Toyota vehicle’s I’ve worked on like a consumer can easily program the keyless remote themselves but not the transponder portion even if the key is all in one design like ours. All I’m saying is if I embed the transponder I should be able to purchase couple of aftermarket keys that don’t have the transponder but has the remote fob electronics and should still be able to lock and unlock with a second remote. Not sure how fiat differs then all other makes in that regard.
Not on the Fiat unfortunately. As I posted in my real early post here Fiat uses a crypto system that's tied to the car's Body Control Module. No fob that has not specifically been precoded for the specific Fiat in question can be authorized to manage the car. With Fiat the two functions are tied together, where the transponder is authorized for the car with the key in the ignition and then the remote functions on the same chip are authorized at the same time.

Fiat keys are a headache that I researched and tested for 6 months. It literally takes about $1000 worth of equipment to precode and introduce a key, which by definition makes it not worth doing. Embedding a single authorized fob in the steering column is the only cheap way of getting extra keys as none of the cut keys need to be authorized. Short of that, spending the $300 or so to get a 2nd key from the dealer is the way to go.

ga2500ev
 

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Not on the Fiat unfortunately. As I posted in my real early post here Fiat uses a crypto system that's tied to the car's Body Control Module. No fob that has not specifically been precoded for the specific Fiat in question can be authorized to manage the car. With Fiat the two functions are tied together, where the transponder is authorized for the car with the key in the ignition and then the remote functions on the same chip are authorized at the same time.

Fiat keys are a headache that I researched and tested for 6 months. It literally takes about $1000 worth of equipment to precode and introduce a key, which by definition makes it not worth doing. Embedding a single authorized fob in the steering column is the only cheap way of getting extra keys as none of the cut keys need to be authorized. Short of that, spending the $300 or so to get a 2nd key from the dealer is the way to go.

ga2500ev
Ahh now I understand wow the setup for Fiat is vastly different then a typical Japanese car. Yea on Japanese cars the car remote keyless and transponder work separate so while the transponder is glued in the remote can be added separately you’re only disabled the security chip part. But great information buddy, I understand it now.
 

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I'm going to explain the entire process to ensure that future searchers coming across this are not fooled into thinking this is as easy as 1,2,3. In short you were lucky.

Fiat uses a crypto key transponder system. There is a secret key that is shared by the car's Body Control Module (BCM) and the transponder. It's a write once system where the key can be written once on the transponder and then locked. After that it cannot be neither read nor changed again.

So the process of taking a blank unwritten transponder, getting the secret key for the BCM, writing it to the transponder, and locking it is called precoding. All of this preceeds what is considered "programming" of the keys, which is simply authorizing a new, already precoded key to the BCM.

So one cannot program a blank key because it's not precoded. One cannot reuse another key because it's already precoded to another BCM.

Fiat precodes by keeping a database of BCM secret keys based on VIN. So they take a blank transponder, precode the secret key, and send it to the dealer. The dealer then "programs" the already precoded key.

The other path, the "lucky one" in this case is to find a locksmith that has the ability to extract the secret key from the BCM. This is done either via OBD port or by physically removing the BCM from the car, extracting the chip with the secret key, and reading it. Once the secret key is in hand, it can be precoded into any number of blank transponders, producing new keys that can be programmed for the car.

I personally tried about 10 locksmiths and none had the equipment to precode from the BCM. In the end, I had it done with the dealer. Cost $280.

Finally, do not break or lose your last key. A Fiat with the alarm activated and no valid key will melt the BCM, permanently disabling the car. The car will have to be towed, the BCM replaced, and new keys precoded and programmed to the new BCM. My best advice is if you only have your last key, only lock the door from the outside and never use the fob to lock. Locking from the outside deactivates the alarm. Losing the last key then eliminates having to replace the BCM. I also had two non transponder keys cut. They unlock the car but will not start it.

If I had to do it all again, I'd likely bypass all the security by embedding the last working fob in the car and driving and locking the car with non transponder keys. It eliminates all the hassle and makes new keys both easy and cheap.

ga2500ev

Where did you get the non-transponder keys? I want a spare key to just unlock the door in case I get locked out.
Your help would be appreciated.

Thank you,
Debbie
 

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Where did you get the non-transponder keys? I want a spare key to just unlock the door in case I get locked out.

Your help would be appreciated.
Here's a sample key from Ebay that actually has the cutting service with it. The essential part of searching for these is to search for "Fiat 500 key blade". A search for just "key" will get you a lot of hits on the fob, but not the plain key.

ga2500ev
 

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I'm going to explain the entire process to ensure that future searchers coming across this are not fooled into thinking this is as easy as 1,2,3. In short you were lucky.

Fiat uses a crypto key transponder system. There is a secret key that is shared by the car's Body Control Module (BCM) and the transponder. It's a write once system where the key can be written once on the transponder and then locked. After that it cannot be neither read nor changed again.

So the process of taking a blank unwritten transponder, getting the secret key for the BCM, writing it to the transponder, and locking it is called precoding. All of this preceeds what is considered "programming" of the keys, which is simply authorizing a new, already precoded key to the BCM.

So one cannot program a blank key because it's not precoded. One cannot reuse another key because it's already precoded to another BCM.

Fiat precodes by keeping a database of BCM secret keys based on VIN. So they take a blank transponder, precode the secret key, and send it to the dealer. The dealer then "programs" the already precoded key.

The other path, the "lucky one" in this case is to find a locksmith that has the ability to extract the secret key from the BCM. This is done either via OBD port or by physically removing the BCM from the car, extracting the chip with the secret key, and reading it. Once the secret key is in hand, it can be precoded into any number of blank transponders, producing new keys that can be programmed for the car.

I personally tried about 10 locksmiths and none had the equipment to precode from the BCM. In the end, I had it done with the dealer. Cost $280.

Finally, do not break or lose your last key. A Fiat with the alarm activated and no valid key will melt the BCM, permanently disabling the car. The car will have to be towed, the BCM replaced, and new keys precoded and programmed to the new BCM. My best advice is if you only have your last key, only lock the door from the outside and never use the fob to lock. Locking from the outside deactivates the alarm. Losing the last key then eliminates having to replace the BCM. I also had two non transponder keys cut. They unlock the car but will not start it.

If I had to do it all again, I'd likely bypass all the security by embedding the last working fob in the car and driving and locking the car with non transponder keys. It eliminates all the hassle and makes new keys both easy and cheap.

ga2500ev
I lost my only key to my 2013 Fiat 500C Abarth......It was locked with remote.....AAA came and opened the car and the alarm went off....I immediatly disconected the Battery to shut it up....I continue to search for the key ....spent 15 hours searching for it so far.......How screwed am I ? The triple a guy told me the dealer charges $1400 to get a new key and I have to tow it there.....i will junk this perfect low miles Abarth before I let the dealer rip me off like that.....Any suggestions anyone? mike in Florida
 

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