1975 F250 Electrical Problem

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Nov 10, 2002 | 09:44 PM

75F250Colorado

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From: Longmont, CO USA

1975 F250 Electrical Problem

When a fuse is not present in the "dash board" lights circuit in the fuse box, the dash board lights are alway lit whether I have the headlights on or not. If the Fuse is inserted, My parking lights are always on, too. My front right turn signal does not work at all. The rear right does, however. Also, the radio stays on after the ignition switch is turned-off only if the headlights are on.

I have replaced the head light switch and almost every bulb in the truck. I know the best thing to do is to grab my multimeter and try to trace down a short, but I figured I'd ask if anyone else has any other ideas before I take that time-consuming task on.

Any Ideas?

Nov 10, 2002 | 10:11 PM

LxMan1

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From: Louisville,Ky.

1975 F250 Electrical Problem

That is very strange. Does all of this occur while the headlight switch is unplugged too? Also, you may want to try the electrical forum, you may get better answers there.
Jimmy

Nov 11, 2002 | 02:48 AM

Torque1st

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1975 F250 Electrical Problem

Bad or broken body ground strap or frame ground...

Have you recently replaced the negative battery cable? Have you added a body lift? Have you replaced the passenger side inner fender? Is your inner fender/frame real rusty?

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Nov 11, 2002 | 12:21 PM

75F250Colorado

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From: Longmont, CO USA

1975 F250 Electrical Problem

>Bad or broken body ground strap or frame ground...
>
>Have you recently replaced the negative battery cable? Have
>you added a body lift? Have you replaced the passenger side
>inner fender? Is your inner fender/frame real rusty?

I have only had the truck for about 2 months. I haven't replaced anything except bulbs and the headlight switch. I'll check the inner fender/frame on pass side, but I don't think it is really rusty.

I have a hunch that something has crossed with the cigar lighter circuit and could be causing it. It is just a hunch considering it had an aftermarket radio. That was going to be my first plan of attack.

I also forgot to mention that the brake light on the dash and the right turn signal indicator do not work either. I didn't know if there could be an in-line fuse or braeker somewhere that could be the culprit.

I also noticed while driving home last night that the dimmer function for the dash board lights does not work.

Thanks for any help!

Nov 11, 2002 | 01:58 PM

beartracks

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From: Albuquerque

1975 F250 Electrical Problem

Whenever I encounter weird symtoms in the lighting circuits I start looking for a bad ground. Things can feed backward through some bulbs and other systems.

Nov 11, 2002 | 03:36 PM

theonlybull

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From: clementsport canada

1975 F250 Electrical Problem

kinda sounds to me like the PO wasn't very good at wireing.... i'd pop out that stereo and unhook all the wires... probably hooked thinks up wrong.

Nov 11, 2002 | 06:36 PM

Torque1st

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1975 F250 Electrical Problem

Most vehicle electrical fires are caused by stereo equipment improperly installed.

Since you haven't had the truck long you don't know what was done. Check the negative battery cable. It should have a tab welded to it part way down that is bolted to the frame or inner fender (I don't remember which).

There should also be a body to engine ground strap. If either of these ground points is bad you can get the weird symptoms you are talking about.

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