Electrical Woes

[blazinid]

I'm new to the Forum and EB's. I've had my 1970 302 3speed (on the floor) for about 2 weeks now. I've already learned alot from reading items on this board, so thanks for that.

To my problem, I noticed I didn't have any tail lights the other day. So I checked the fuse, all looked good. Pulled the bulbs and they were both toast. Replaced them and everything worked.

Drove it last night and once again no turn or break. Pulled the bulbs and they were burnt out again. Put a couple spairs in and I noticed with the switch off, when I hit the break petal I get all kinds of lights coming on. Dash, markers and tail lights.

What the hell is going on? Please help, I'd like to drive my new toy but don't want a ticket

Thanks

 

[73azbronco]

You have a short. Check the usual places, firewall hole where wires go through, under dash by brake pedal, others?

 

[blazinid]

What am I looking for? Bare wire rubbin against metal?

 

[blazinid]

Does anyone have a picture of the fuse box with a discription of what fuse is for what? As far as I can tell there are no labels on the box its self

 

[70_Steve]

Does anyone have a picture of the fuse box with a discription of what fuse is for what? As far as I can tell there are no labels on the box its self

Lots of good info on N8's Site.
http://www.wsu.edu/~i6735189/diagrams.htm

 

[blazinid]

thanks.....looking at that makes me scared.....hold me

 

[74BroncoCO]

I feel for you. Most guys on here hate Electrical gremlins like you describe. I would trace the wires from the tail lights forward. Check your grounds along the way too. Good luck!

J.D.

 

[73azbronco]

After thinking some more, start follong the brake light wiring, it hgas to be the short. you might want to go underneath and check the wires that run down the frame toward the back, thats where mine went toast, rubbed through to nice shiney copper. you may have that and the marker lights shorting, thereby feeding juice to the sidelights and dash lights.

Most hate these problems, me too, but i find it pretty easy to start following where a wire goes and where it's been rubbed through...

 

[Broncobowsher]

Also check the grounds at the tail lights.

With an open ground power from the brake lights will go to the brake light filiment. Without a good ground it will search out other grounds, like backwards through the park light filiment energizing the parking curcuit.
If the gauges are not grounded good the running light curcuit will try to find it's ground, possibly through the front turn signal indicators, power them up dimly as they ground through the front turn signal bulbs that you will never see light ub as the voltage drop isn't enough to light up the element by that time.

Yes eletrical stuff is interesting. When you get wierd problems, generally it is the grounds.

As far as suddenly burning out bulbs, check the voltage regulator. If it is bad you could overcharge the system and dump some stupid voltage (17+ volts) through 12V bulbs and they will toast. Oh, a bad ground on the voltage regulator will cause an over voltage condition and very likely burn out the regulator at the same time.

 

[HoosierDaddy]

I noticed my headlight switch was just a little loose on the back side of the dash. Moved it around a little and tightened it up and suprise ! my tail and dash lights started working. Never had a problem burning up bulbs though.

 

[blazinid]

tonight i'll crawl under and start tracing wires back. Should be easy enough to find where the grounds are attached and make sure they are secure.
Thanks for all your help

 

[Explorer]

Check the bulb sockets for corrosion, if the contacts are shorting together, applying brakes will backfeed to the other lights.

 

[blazinid]

Well I started looking around last night, didn't have a chance to check everything yet. I regrounded my pass. rear light. The body was a bit rusty there so sanded it down and put a new screw in place.

Looked at the license plate light. It wasn't hooked up. So the harness has a pig tail coming off of it that is just hanging there. There is also a ground wire screwed to the body, but no wire coming off of it. I would assume that was for the license plate light at some point??

I also added a 10ga wire from my battery to the body, figured that couldn't hurt anything.

So far still have all the same problems, but still have more to check

 

[mr incredible]

make sure all of the bulbs are the correct ones for those sockets !!! it is a ground problem ,,, one or all of the lights arent getting a good ground ... might be needing a new body ground ..... battery to body ..... to frame ....