iso9001 said:
So I decided a transistor would be a good idea. I asked somthing about the problem and someone told me an N-Channel Transistor would allow me to use 12V through it but be triggered by the 5V output of a pic.
But I figured that now, I'm not sending 12V throught the transistor, I'm using it to connect 2 grounds. (see diagram)
Can I still do this?
You don't need an FET, you can use a normal transistor, simply feed the base from the PIC via a current limiting resistor. It's also ESSENTIAL! that you fit a diode across the relay coil, cathode to 12V supply, this absorbs the back EMF as the relay turns off, otherwise it will destroy your transistor or FET.