head unit shuts off with headlights

[choochooSS 10+ year member]

i out my pioneer p640 hu in my 92 blazer today and when i went to leave tonight i turned on the headlights and the f**kin hu shuts off and wont come back on unless i trun the healights back off

i cant figure it out

at first i found the solid power wire, but i couldnt find an acc wire so i just put it straight into power wire and i just figured id shut it off everytime i got out sense im not gonna have the truck for very long.

after i discovered my problem i thought that runnin the power wire straight out of the battery terminal of the fuse box would fix the problem but it didnt

so what do i do now, it kinda sucks not being able listen to my stereo if its raining or its dark

WTF????

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[B&R Innovations]

Man thats really weird

You dont have it running into a dimmer relay do u?

Otherwise maybe your battery/alt is so bad that the lights take up too much power and the HU cant even run

 

[choochooSS 10+ year member]

its not on a dimmer relay, its a power wire straight from the fuse box in a batt. terminal

the alt/batt isnt bad i dont think cause it worked fine with the stock unit.

what do i do now?????

 

[choochooSS 10+ year member]

TTT im needin an answer pretty quick like

 

[more_spl 10+ year member]

severe voltage drop? idk how headlights can cause that, but too low voltage can casue HU's to shut off

 

[eengrms 10+ year member]

Find a different power source for the HU. Why did you go to the fuse box in the first place and not use the stock wires?

 

[choochooSS 10+ year member]

i tired using the stock wires but it didnt work

so i went to the fuse box

i finally got it workin i never really figured out the problem but it works now

i just ran all new power and ground, there was only one batt. terminal on the fuse box that worked with the headlights

it took me a while to figure that one out

 

[AtomicGuY 10+ year member]

The best place and most easiest place to run the headunit from is the Cigarette lighter. Its 12V and all you got to do is make a Y split and your done.

Cigarette lighters even come with a Ground //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif so it makes things even easier.

AtomicGuY

 

[B&R Innovations]

Ok why would u want to run wires off your HU into your cig lighter...its be ugly and annoying. and prett unuseable

 

[choochooSS 10+ year member]

i think hes talking about the wires inside the dash that lead to the cigarette lighter

maybe, i dont know

 

[eengrms 10+ year member]

Originally posted by choochooSS i think hes talking about the wires inside the dash that lead to the cigarette lighter

maybe, i dont know

Yeah I'm pretty sure that's what he meant. I do, however, not agree with him. The cigarette lighter has to be the worst place imaginable to take HU power from. Do yourself a favor and find the ignition wire and +12V constant wire at the steering column and take fused lines off of that for your HU power if you have to. Why don't your stock wires work again? Have you checked the fuse?

 

[choochooSS 10+ year member]

the stock wires must be onb a dimmer relay i didnt think they were but the have to be

like with the stock radi o the lights on it would dim when u truned on the healights so apprently my pioneer wasnt gettin enough power

 

[eengrms 10+ year member]

The light dimmer circuit that goes into a stock HU is a completely different wire, and most cases a completely different harness. That's usually the small, two-wire harness that plugs into the middle of the stock (in most cases). You shouldn't have hooked anything up to this. When you upgrade that harness always goes unhooked. I've never heard of an aftermarket with a dimmer interface (although I'm sure it exists). As to the rest of your problem, it sounds like you got it fixed. True?

 

[choochooSS 10+ year member]

yea i fixed it

 

[AtomicGuY 10+ year member]

Originally posted by eengrms Yeah I'm pretty sure that's what he meant. I do, however, not agree with him. The cigarette lighter has to be the worst place imaginable to take HU power from. Do yourself a favor and find the ignition wire and +12V constant wire at the steering column and take fused lines off of that for your HU power if you have to. Why don't your stock wires work again? Have you checked the fuse?

Well, I guess it all depends on the type of vehicle you plan on runing the HU power from. Whats wrong with the Cigarette lighter??? Its fused with 20A, and its available in over 95% of all vehicles.

Now behind the dash, you'll never see the wiring job and plus the ground is already there.

In my truck, the lighter fuse is easy to get at in the fuse box and makes the perfect install. You cant even see my cig lighter wiring job,, its all behind the dash.

ATomicGuY