Making a Smaller Passive Key Fob

[cbrookre]

FINISHED! SUCCESS!!!

Forget about soldering. Forget about nylon washers. I just went for it with a pair of needle nose pliers. Gripped the whole button assembly square head on and gave the smallest of pulls. Came right off the board. Could not have been easier. They are barely stuck on at all. Used the needle nose pliers to just knock down any remaining pointy stuff (there wasn't much). Reassembled the battery, etc as before, and . . .

Ta-Da!

It worked perfectly. No buttons. Just a passive key fob that fits in my wallet. As long as I have my wallet on me (and I always have my wallet on me) I can use my car.

Done. End of story. It's a really simple $50 mod.

EDIT: Here is a better photo of how the battery is hooked up (before I applied the tape)

Just for other people's benefit, the pliers pull off method is not recommended. You pulled the metal pads off the board so there is no going back, and it is possible that you could short them doing this (pull up the metal trace attached to the pad and it touches the neighboring pad). But glad it worked for you!

Sponsored

 

[mustang1]

this looks like a clean way to remove a surface mount chip. $15 kit on amazon, with high rating.

SMD Removal using a Chip Quik kit
[ame]

 

[cbass]

I'd be in on a 3d printed case for the guts that still allows me to remote start. Only thing my key gets used for.

 

[DrEverettScott]

Sub'd. Great idea

 

[chrisgonzales]

oooh i like this idea lots, i have access to a 3d printer but only can do basic shapes, i use sketchup for most of my test ideas. i need to get an extra key now and try this out.

 

[bluehorse]

bump. This would be an awesome idea to make it even smaller. I always wanted to figure out how to make it into a watch just to feel like 007. Not sure thats possible but one can dream.

 

[Excelerater]

nice work,owning two fords id say the key FOB is stupid in shape and size
!

 

[bluehorse]

well i did this yesterday. it works. but my $90 Carbon fiber RFID blocking wallet works better :frusty: the new smaller key doesnt work while in my wallet. Interestingly, it works fine to unlock it and I can start the car but the second I close the door it does the double honk and states that no key is detected. If i take the key out of my wallet, it works perfectly. its weird how the RFID blocking property of the wallet "kinda" works.

 

[chrisgonzales]

Love this idea so much that we have a 3dprinter at work that i'm working a small case for the board and battery. Will be slightly thicker hence not thin as tape but thinner than the balloon that is the current fob

 

[vernonator]

Love this idea so much that we have a 3dprinter at work that i'm working a small case for the board and battery. Will be slightly thicker hence not thin as tape but thinner than the balloon that is the current fob

You put that up for sale and I know I will buy one....

 

[JakePSD]

Really, if you can just rig up the power source you could just find and/or alter slim profile case of some sort and put it all in there. The thickness of it is a bigger problem than the length (that's what she said).

:lol::lol::lol:

You put that up for sale and I know I will buy one....

I'd highly consider it. It would be cool to somehow figure out the circuitry and make it more compact, with a smaller battery, and could maybe be the size of a large coin or so. Think of all the possibilities! You could make one that looks like a normal souvenir key chain but it is actually the key to your car. Or something that is roughly the size of a normal key so that the normal monstrosity that is what we have now is gone and fits on a keyring like anything else.

 

[Stangnut]

For the battery you might look into what a modern garage door opener remote has in it. You can't even replace the battery in those anymore so I'm guessing they must last a long time now.

 

[Merchant Marine S550]

Love this idea so much that we have a 3dprinter at work that i'm working a small case for the board and battery. Will be slightly thicker hence not thin as tape but thinner than the balloon that is the current fob

Great idea. I'd love to see the final product!

 

[timd38]

Great idea. I'd love to see the final product!

It is the picture with all the black tape on it.

 

[bluehorse]

Love this idea so much that we have a 3dprinter at work that i'm working a small case for the board and battery. Will be slightly thicker hence not thin as tape but thinner than the balloon that is the current fob

SHUT UP AND TAKE MY MONEY!!!!! I want this!

Sponsored