Radar detector help

[MNlotus]

i got a radar detector for my seven and i finally got all the parts i need. i got the cigarette lighter and it has a place for ground and +12v to connect to it. Where can i find this at and how do i go about doing this? i'd prefer that it turns on and off with the ignition but it doesnt have to, i can turn it off and on manually. i do know the basics of electrical systems, and have a fluke 87 for testing? Can anyone help? im not getting too much help over at usa7s.com

[charliex]

i usually use the fuse box on the lower pic, i think i posted a writeup of it for a cluster install brb.

[charliex]

yep, there is a ground on the obd ii pin 4 and 5 too. this is a switched 12V+

[charliex]

and for completeness. just vampire tapped. black wire pin 5 GND

[charliex]

oops is this for your 7 or for the elise if its the 7, case ignore the pics

[MNlotus]

yeah its for my seven, there are fuses in every place on the fuse box? can i still do it through the fuse box?
can i just tap into the back of the fuse box where all the wires enter? if i find a ground and +12v in the back,will it work if i tap it?

[charliex]

yeah i'd imagine so, but you'll need a voltmeter and just check that red wire in the middle pic, top fuse box.. see if its a 12V acc switched. unfortunately i dont have diagrams for that car.

[MNlotus]

i got my test light. the bottom two fuses turn on and off with the ignition. is this where i should tap in?

also real close to the fuse box is a bolt that is on the body, which holds the windscreen/windkick on. i tested it with my test light and it is a groung. i can use this for my ground right?

[charliex]

just be careful about the load you put on the wires you find as 12v, since you may not know what the circuit is for, a radar detector problem isn't much of a load but don't do a homer simpson.

depends on the way the car is made, engine/ignition type/etc if it has a seperate digital ground, then i'd look for that, if its all the same ground the chassis is ok.