Constant power source (+12Volts) at the trunk

[camree99]

I am trying to install a GPS system with a pc unit (not the portable ones) and I need a constant +12 Volts power to be connected to the pc unit. I'm wondering where I could tap from the trunk area even when the ignition switch is at "OFF" position. I was trying the courtesy switch of the trunk cover, but I get 0 volts when the trunk is open.

thanks very much for reading! hope somebody could give me some sound advise.

[Eye8Pussies]

to the best of my knowledge, there is no constant power source in the back of the car

all the lights are hooked up to relays, and the trunk light only gets power when the trunk is open.

I presume that you don't have a sound system in your car then?
it seems like you'll have to run a fused line from your battery to the trunk, or the closest constant 12v would be from the dash area.

[camree99]

thanks very much for the advise! anyway, any idea what current rating i need for the fused line?

actualy after i downloaded the electrical wiring diagram, i figured out why i get 0 volts when trunk is open. so what i'll do, i'll tap from the trunk lamp side.

thanks again!

[toyomoho]

See if you can tap off the power going to the trunk light switch located below where the trunk latch enters the frame.

[Eye8Pussies]

hmmm....you know....you just made a good point....

I had presumed that the relay would be sending power from the front of the car, but that wouldn't make much sense at all. There has to be a constant 12v going to that relay in the back of the car that is activated by the trunk opening....

Good thinking.

[toyomoho]

Just assumed this would be the straightforward way to do things. Perhaps if Lucas had designed the wiring, but then the light might not work at all. The antenna motor may also have a constant source of DC power.

[88 LE]

Originally Posted by toyomoho

See if you can tap off the power going to the trunk light switch located below where the trunk latch enters the frame.

Tapping off the switch won't work. It works off a ground. IE: negative trigger.

[camree99]

Thanks very much! I tapped from the trunk lamp supply and it worked!

[WhiteRabbit]

^thats a constant 12v???

[camree99]

actually yes. you can check the wiring diagram. just make sure you tap before the bulb, which makes a parallel circuit when it is turned ON when the trunk is opened.

[WhiteRabbit]

cool, good to know