2004 XC70 Replacement keys

TCKibe · Post by **TCKibe** » 20 Mar 2014, 16:52

Hi I am new to the forum and Volvo's. I've owned just about everything else. I just bought an 04 XC70 that only came with one key. My question is can I have two keys cut and secure my coded key near the ignition lock cylinder and use the dumb keys to start the car? The alarm guys we used at our shop used to put a GM VATS key under the column cover for remote start systems.
Thanks for any help. Tim

swimNdrive · Post by **swimNdrive** » 20 Mar 2014, 23:07

I have heard some people had done it. For this car, however, when I tried that, I was having hard time to put the transponder in a place that is secure and functional. It is very sensitive about the location where you put it. I could make it work, but have hard time to make it work consistently. So I gave it up. You can try it out. If you find a good way to make this work consistently, please post some pictures.

TCKibe · Post by **TCKibe** » 21 Mar 2014, 04:27

I think I will give it a try. I can always have the keys programmed later. If it works I'll post pics. Does anyone know if the keys emit a signal if they aren't programmed? I was thinking of possible interference.

swimNdrive · Post by **swimNdrive** » 21 Mar 2014, 23:36

It won't interfere.

Post by **vtl** » 22 Mar 2014, 07:05

It is fairly easy to disassemble immobilizer antenna module and desolder antenna ring.

Two leftmost pins w/ some black plastic around is LED, next to right are antenna pins. You can either try to pry antenna out of plastic or replicate antenna yourself, solder it to long wires and hide together with key anywhere you want.

By the way, Megamos Crypto protocol has serious security deficiency, the flaw should be published soon. That could lead to an extra auto-thieves attention to Volvo, VAG, etc. And provide Volvo enthusiast an easy way to overcome lost keys problem

swimNdrive · Post by **swimNdrive** » 22 Mar 2014, 23:57

vtl wrote:try to pry antenna out of plastic or replicate antenna yourself, solder it to long wires and hide together with key anywhere you want.

Hm, that's an idea. From your picture, you can tell there is no room in the ring for the transponder. I tried to put it outside of that, but it was not reliable. I have already had a key made. I will keep this in mind in case I need to go this route.

TCKibe · Post by **TCKibe** » 26 Mar 2014, 03:53

Well it looks as if the key has to be inside of the antenna loop to activate . I'll try the above when i get some cash and a used antenna. Meanwhile it's motor mounts next. I've done Timing belt-waterpump, front struts and mounts, lower control arms and ball joints and have to locate an exhaust leak near the back of the head. Anything else?