Keyless Entry Subaru

Eyyy good news, the key works superb on the 3.3V supply from the arduino (altho teoretically it uses a 3v battery) so protyping is super easy, also the buttons to close/open the car work nicely even when the keyfob is in the car, so now i just have to hook up some transistors to replace the buttons, and a relay for the 3.3v power supply, then i can test it with a button or something else i have lying around (before i buy a rfid reader :P)

also the battery terminals in the key are laaaarge, so no problem soldering, the button terminals however… not sure how to go about doing them… also other soldering points very close to them, so i cant really over dimension it…

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I used a transistor to control power to the fob.

Well, killed the keyfob with heat -.-

F in the chat

got wires onto the battery terminals and that worked, got wires over one of the buttons, that worked, tried to get wires onto the second button, PCB got darker, and on the other side of it was an IC -.-

Did you remember to remove the S3 jumper?

what is an S3 jumper?

cheapest replacement key (cuz of programming) is around 350 usd, soooo the project is on halt indefinetly :joy:

Oop I’m slow you’re using an arduino, I was thinking about the xEM AC

yeah i was thinking id get it working just with an arduino first, then buy the xEM AC later, so i dont buy it without using it sorta

Good call i suppose

I FUCKING FIXED IT :joy: :rofl: :grin: :grin: :grin:

EDIT: A resistor fell of im dead… Picture for reference, that mini thing was where the same color is on the PCB… Right enxt to the button, were talking like a few mm


I’m currently planning a build of this style system, but for a proximity keyless entry (basically we do the battery thing but toggle it on/off for implant taps).

This one’s for a Model S though.

like this?

sorry no… only the model 3 supports contactless smart cards. the model s uses a 125khz texas instruments 40 bit challenge/response tag in the keyfob.

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We had hoped to use this… But no, he’s got a Model S. Too old.

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Just wanted to see how things are going. Is the system still functioning well? :smiley: