12V Power Source Wiring

[methodical]

Ok my car does not have a cigarette lighter... I have XM radio so I needed to add a 12V power source. There was a harness with 4 wires (which i guess went to the missing cig lighter?). I cut the harness off and used a positive and negative wire to hook up a new 12V power source. I fused the positive wire and all. The power source works and the XM radio powers up fine.

My problem is when I turn on my lights the XM radio powers off and my D4 light (auto tranny) in my dash starts to flicker. Anyone know what is wrong here?

[ProJect]

the problem is that you got the wire for the parking lights for your 12 volt source, the wire you got is red/black and it only has power when your parking lights are on, and when you shut them off thats why your xm is shudding off, run your 12 volt source to were you fuse box is, there are i belive 4 or 5 empty spots were you fuses are that are power, 1 is parking lights,the other is 12 volt switched and there is a constant, there is were u tag the power for your fogs,bumper pole etc, so grab your power from there and youll be coo. -damien

[methodical]

Well its when I turn my lights on the radio shuts off... With the lights off it works fine... I believe the wire is red/black though. I get what you are saying though. Thanks.

[accordztech]

u tagged the dimmer for the lights, when its on it turns and varies from ground to a positive with the dimmer.

id chassis ground the black wire just incase you thought that that wire was a TRUE ground in which it isnt when the parking light comes on, as i said with the dimmer, fadding from ground to positive.

do you have an aftermarket deck? even a factory you can do this, take out the deck, should be easy especially if its aftermarket, and tag the red wire. if its factory i forgot but its one of those =-)

usually the xm units are ok with a 5 amp fuse if you got anything higher than that in there =)

IMO running to the fuse box and shoving it somewhere is kinda ghetto no offense.