I'm hardwiring a device in my new to me V70 that I am fixing up. I want the device to shut off when either the engine is off or the key is out. Either one is fine - it just can't be draining my battery constantly when parked (especially in the cold where I am). This is usually pretty easy and I've done it on a few different cars, including an other European (German) car. I brought the wiring to the fuse box on the driver side of the dash. I went with the Phone circuit, since it was completely unused, but it still sends power, even when the key is out. So I decided to piggy back onto the sunroof circuit (since I'm not drawing any current, really). I know the sun roof circuit (and windows) work after you shut off the car, but stop after you open and close (ie leave the car) - so I thought this would be good enough. However, it's still powering the device from this circuit, even after the sunroof stops working. It must be on a relay on the other side of the fuse box that opens the circuit when the door is opened, because at the fuse box it's still pumping away to my device. It's looking like all the circuits stay closed (on), I'm hoping I'm wrong though - I don't want to have to get too creative and I already brought my wiring into here.

Does anybody know any circuits that will automatically open (shut off) at the driver's side fuse box, when the car is off or when the key is out? I'm just grounded to a bolt and trying to tap my hot wire into a leg of a fuse, at the moment - hoping I don't have to tap into an OEM wire.

Any help is appreciated. Thanks!

 

Later last night, I started to wonder: Are the relays for opening and closing all the circuits on the ground side instead of the hot side?

I've seen that once before in a car (the horn was floating from the ground of the chassis via insulating paint, and had a switchable ground wire running to it, but once the paint got old and flaked away, the circuit was permanently closed and the horn wouldn't stop). I'm hoping that's not the case here; I don't want to have to go looking for ground wires and tap into them.

 

Update: Just in case anyone is trying to do the same thing... Rather than going through all the circuits in that fusebox for a circuit that opens when the engine is off, I realized there was another fuse box (with micro fuses) close by in the footwell, where my wires could easily be fed to and still reach. There seem to be lots of circuits here that turn off when the engine does, I tied into circuit 11 for the 12 volt accessories, and it worked perfectly. I did have to use an "add a fuse" though, because the mini fuses are too small to tie onto a fuse leg, like the ATO size fuse. I had to modify the add a fuse, as well. But everything is clean and working 100%.