The extra original Volvo key for my wife’s 2007 Volvo XC-90 works just fine except that the key wouldn’t stay inside the shell and as soon as you put it in your pocket or laid it down the key would fly out which is uncomfortable to walk with obviously. So I ordered one of the cheap Chinese knock offs on Amazon. No directions or anything like that and I had no idea you had to use a hacksaw to get the front of it cut in half to retrieve the key you can see the video instruction below 👇 but word to the wise there’s a little transponder in there. Again something I didn’t know about which is why the car wouldn’t turn on but here’s a question I located the transponder the next day after I put the new key together and I put it in my hand with the key fob as I turned the ignition and nothing happens and it’s exact same distance from the circuit card as it is if it was actually inside the fob but ignition wouldn’t work . Could someone please explain to me how being sandwiched in between two pieces of plastic with no electrical connections makes any difference then physically being in my hand exact same distance from the circuit card I can’t figure out how this thing works🤷🏻🤦🏻

https://m.youtube.com/watch?v=VrQ4ITM00WA

 

The transponder from the old key has to be close to the antenna ring - The circuit board in the remote section is for remote lock and unlock. The transponder is for the immobilizer so the car will start.

The antenna ring is the lighted circle that surrounds where the key is inserted.

 

wow thank you that does make sense and of course being that the transponder was just held loosely in my hand it was toward the backend of the fob so I wouldn’t lose it obviously what it inserted it’s within 1 inch of the antenna ring. if you don’t mind me asking how exactly does that transponder work does the antenna ring send out a code request that that transponder identifies a specific code this is the best I can find via Google: https://www.easytechjunkie.com/what-...ransponder.htm

 

Don't know - never needed to understand how it worked, just how to diagnose what's wrong and fix them.