headlight switch and stereo

[monterey1962]

As you know, I installed a Pioneer CD/stereo unit this past spring. I wired it properly. I know I did.

Recently, I discovered the following:

1. Turning the headlight switch to dim the dash lights turns the stereo off at the halfway point.

2. With the engine off and the key out of the ignition, you can turn the headlights on and the stereo will have power.

Does anyone know of a reason for this? Even if I wired something wrong, how the hell is the headlight switch even effecting the stereo power supply?

[Grand Marquis GT]

Its the ground.

Wire the stereo ground to a regular ground, like the chassis.

Problem solved. Mine did the same damn thing

[monterey1962]

I grounded my stereo to that plate under the dash with all the tabs on it. Do you mean I should ground it elsewhere?

Do you think it will damage anything if I leave it the way it is for now?

[85crownHPP]

thats wierd!

At first I would say, 'are you sure you didn't wire the stereo's ignition turn-on line into the car's illumination line???' - Becuase that IS connected to the headlight switch (through the dimmer circuit), and IS a wire back there in the factory stereo wiring harness.

But if you are sure, then you're sure Try giving it its own ground and see what happens.... if it fixed Toms, maybe it will fix yours.

[85crownHPP]

Thats where mine is grounded... if your wiring is right, all that leaves is an internal short or break in the stereo connector or its internals.

[monterey1962]

At first I would say, 'are you sure you didn't wire the stereo's ignition turn-on line into the car's illumination line???' - Becuase that IS connected to the headlight switch (through the dimmer circuit), and IS a wire back there in the factory stereo wiring harness.

. . . . . . :confused: . . . . . . Maybe I'm not so sure now. But I tested the wires to find which were hot with the key on and off before hooking it all up. I thought I had the right one's figured out.

I think I tapped into the green wire and a yellow wire. It'll have to wait 'til the dash has to come apart again. If I have time, I'll try changing the ground location.

[Grand Marquis GT]

Ah a wiring harness? Thats not fair!

I had to wire all my stuff up the old fashioned way

[monterey1962]

I just remembered, Tom, you and I have the same stereo. I'll have to try changing the ground for sure, now. Thanks.

[85crownHPP]

do you have auto lamps??? maybe the headlights came on when you turned the key on.

[monterey1962]

I have the switch for daytime running lamps, but I have it turned off. I found out that the stereo stayed on when I parked on the side of the road and left the lights on so traffic would see me. I turned the car off and pulled the key, but the stereo stayed on.

[gadget73]

Sounds like the stereo remote wire is connected to the dimmer circuit. Running power to the remote wire will make the stereo turn on even if there isn't power anyplace else. Try unhooking the blue wire on the stereo if its connected into the factory harness and see if that fixes it.