[BigChief]

I only have one key for my Fortwo. If I copy the metal part of the key only, and take the chip part of it out and glue it near the ignition port, will that allow the car to start even if I'm using other "dumb" key copies? Does the RFID require a charged coin battery, or is it passive like RFID credit cards?

These smart ignitions are too smart for their own good. Who's going to hotwire an electric car that drives 60 miles on a good day?

 

[smark]

Give a try!

 

[DudeInTheSmart]

The exploded view shows a battery in the key. Not sure if that is for the remote, or the imobolizer. Worth a try. Do you have a 451 or a 453, the technology is different between them.

 

[Miss Mercedes]

Someone on this forum did just that, actually. They added a plastic cap to the top of the blade to make it look more visually appealing, too. I'll see if I can find the thread.

Edit: It was Cubefx! Here's how to do it:

Fobless key

My 4 years old son loves to drives with me in the smart. I noticed one problem. He likes to swing his legs and couple of times I noticed that it was too close to the key. I ordered the spare blade from the dealer. Dealer charged me $57. For some reason I got TWO blades for that price. Not...

www.smartcarofamerica.com

The big thing is that the fob needs to be there when you start the car, or the immobilizer won't be disabled.

 

[BigChief]

Thanks, the one thing the Cubefx solution didn't cover is whether the RFID is active or passive. So I just did an experiment myself with removing the battery and circuitboard. The RFID does indeed still work and start the car if held next to the key without battery, but it needs to be extremely close to the key, and even the orientation matters. I'll see if I can get a tiny plastic project box to put the PCB inside and glue it to a "sweet spot" near the keyhole that the immobilizer can receive consistently.

 

[DudeInTheSmart]

How do you plan to lock your doors? Or convertible so you never lock them.

 

[BigChief]

Doors can be locked physically, the smart cars come with a plastic cap covering up the key hole near the door handle, but you can pop it off and there's a keyhole underneath.

 

[BigChief]

But if anyone knows of like a mail-in service where I can send my original key and the eBay copies to have those cut and programmed, I'd be interested. Local MB wants over $350 to copy a key and they won't program the eBay keys.

 

[jwight]

Doors can be locked physically, the smart cars come with a plastic cap covering up the key hole near the door handle, but you can pop it off and there's a keyhole underneath.

The door only unlocks with the physical key, because it pulls a Bowden cable. The key can't push the cable to lock the door.

 

[jwight]

But if anyone knows of like a mail-in service where I can send my original key and the eBay copies to have those cut and programmed, I'd be interested. Local MB wants over $350 to copy a key and they won't program the eBay keys.

Check out SOS Diagnostics: S.O.S. Diagnostics - Automotive Programming and Diagnostics

 

[DudeInTheSmart]

That works if you have a 451. As I understand it, the 451 is prgrammed to work with the car. For the 453, the car has to be programmed to recognize each individual key.

 

[Miss Mercedes]

Doors can be locked physically, the smart cars come with a plastic cap covering up the key hole near the door handle, but you can pop it off and there's a keyhole underneath.

If your idea is to leave the separated key in the car/ignition then lock the doors then you will need a working fob. There is no manual way to lock the doors, even through that keyhole.

If you do the exact thing that Cubefx did then you can have a separated key and working locks... but to me that seems like a convoluted solution to the problem of losing keys. I mean, you'll now have multiple pieces of key to keep track of!

 

[vadsoom]

But if anyone knows of like a mail-in service where I can send my original key and the eBay copies to have those cut and programmed, I'd be interested. Local MB wants over $350 to copy a key and they won't program the eBay keys.

This isn’t possible. The car and all keys must be present when the keys are programmed. I have a MB Star clone and have used it to program lots of keys. If a key isn’t present when the SAM is programmed, it won’t work in the car, even if it previously did.

Use caution.

 

[__dlan__]

Try reaching out to locksmiths on yelp, etc. I got new keys made for a Subaru a year or two ago and they got me 4 keys for much cheaper than the dealership price. They might even do the eBay keys for you.

 

[jmartinsmart]

You still haven't stated if you have a 451 or a 453... this makes a world of difference when it comes to us giving proper advice. The two cars ignition systems are different.

I have owned both a 451 and a 453 but only needed to do key work on the 453... it was quite a job, and $450 later (even without a dealership), I had three working keys (already had one, but added two more).

For example... people tend to think that the key is somehow programmed, when in fact it is the Car that is programmed to accept the key. As @vadsoom stated, ALL keys must be present when programming... even if you are only adding one new key to the car's computer.

Jim

 

[wmf2008]

Try reaching out to locksmiths on yelp, etc. I got new keys made for a Subaru a year or two ago and they got me 4 keys for much cheaper than the dealership price. They might even do the eBay keys for you.

i have had additional keys made at a local locksmith and a local ACE hardware, so no problem getting a key even if you don't have the old one

Bill

 

[DudeInTheSmart]

The door only unlocks with the physical key, because it pulls a Bowden cable. The key can't push the cable to lock the door.

This is what i thought as well, but I was just flipping through my user manual (need to replace a brake lamp) and noticed for the 453 at least, there is a seperate point on the trailing edge of the doors where you can insert the key to manually set the door to locked and it will then lock when you close it. Not what I would want to do every time I leave the car, but I did not know this was possible.

 

[DealMeIn]

Presumably that's to lock the car if the fob stops working and you need the car locked. For the 451, you have to use the lock button in the car with the ignition key at position 1 to lock the car after you exit the vehicle without the fob.