I am still rebuilding a 67 FB conv. I have transplanted a 74 455 that is rebuilt.
The electrical consist of the main harness that came with the car, a new engine harness, used front lighting harness I bought from this site and a new rear harness. I started the engine for the first time this weekend and all went well. I turned the key and after a couple pops away it went. However when I started checking the other systems I found that I had no power to any of the pins on the drivers side of the fuse block. The other side of the fuse block worked fine because the engine started just fine. I have a new light switch and all fuses have been replaced. I tried it with the switch installed and hanging free under the dash just in case there was a problem with grounding.
What now, please help.
I have the car ready to start installing sheet metal for body work and the interior is gutted so I can still get to everything.
Thanks
EB

you may have a problem with the fuse box

That is what I am thinking but does that mean replacing the whole under dash wire harness? Or can it be fixed if it is just a short or broken connection?
EB

I had a bad fuse box a few years ago...bought a used one, spliced it in to the harness , just outside the box...works fine.

I have been out in the shop playing around with it and have found that the 20A fuse on the bottom shorts and burns out.
The markings on the box are not readable. Also the one I can read says instrument and it has no power to it. Could the instument fuse make the lights not work? Can someone tell me what the fuse is on the bottom of the box. I am hoping that I can fix it because this harness is not cheap!
Thanks
EB

OK, I have decided to replace the dash harness. The two I picked are American Autowire and Wireharness.com. I picked them mainly for price.
Any feedback on these? I am going with the stock harness not the updated one.
EB

wiringharness.com is what I used, plug and play, zero issues.

One variation from the original harness that I didn't understand is that there is a provision for a neutral safety switch (two thick purple wires) near the pedal bracket. Since the '68 with manual had no neutral safety switch, I had to jumper this connector to allow the starter to engage. According to their catalog it is the correct harness for the application (floor shift, gauges, manual trans).

Before spending money on a new harness, why not find the short in the harness you have?

Look at the Electrical section of the Firebird Service Manual Supplement - Firebird Electrical.

The schematics are on pages 12-2 through 12-6 (fuse block on page 12-4), and the fuse layout is on page 12-17. Hopefully this will help you make some sense of what is going on.

Pete

I do plan on taking it out and looking at it to see if there is a broken connection or wire before I buy a new one. It looked fine when I put it in but who knows!
Thanks
EB

It could be as simple as the lighter plug shorting out, or a courtesy lamp socket, or even the glove box lamp lead. You may want to find a small 5A or so plug in self resetting circuit breaker to use for testing. Look to see what ISN'T working, the breaker will trip then reset, eventually you wil get through your circuits. Use the wiring diagram to narrow it down first.

I printed out the pages Pete sent and am going to go thru the harness this weekend. It cold as H*** here and it takes too long to heat up my shop after I get home from work to do it during the week.
It would be nice to just find the problem and use that money somewhere else on the car.
Thanks
EB

Cold... in Texas? Vikki gave some sound advise. Trace down what's not workin' and trace it back.

Also take a look at the wiring diagrams in the Library at the firstgensite. They are in color and might be easier to follow.
http://thefirstgensite.com/html/librarydex.htm

Pete

FWIW, one side is hot all the time.
The other is only hot with ignition key in the on position.

Yep, cold in West Texas. 32 for a high here today 20 tonight, same tomorrow and snow on friday!
I will trace it out but for the most part it is everything on the outside plug of the fuse box.
I have the color diagram and it is nice.
I did check it with the switch in both positions but never got anything to the light side.
The engine does start and run and the alt. shows charge so that side does work.
We'll see.
Thanks to all.
EB

I have been working on this now for a few hours and I have more questions, some may be stupid!!
First, do you have to have all systems plugged up? Like turn signals, dash etc. I have everything in where it can be plugged up but I was trying to eliminate some things to make it easier to find the problem and then plug them in one at a time.
The strange thing is I went out there this AM and got my brake light switch, tail lights and all of the fuses working and then later NOTHING!! I did not change anything in between then and now. I have everything grounded, frame to body-body to engine etc. Any suggetions??

Thanks
EB

Wiggle your headlamp switch. A failing rheostat can cause all sorts of issues.

I have a new headlight switch and it looks like it works at the switch.
I don't have a battery in the car and have been using an old battery that needs a charger on it to even make the starter click. Could it be part if not all of the problem if the battery is not good and the charger can't put out enough to power up the system?
I am not getting anywhere on this and I hate to buy a new harness until I find the problem.
I know getting a battery would answer this question but I will be doing body work on this car for a few months and was trying to avoid buying a new battery until I new I would need it.

EB

Do you, by chance, install the electrical junction block that goes on the radiator support behind the battery? Then connect the brown wire that comes off the positive terminal?

I did install the junction box, however my wire going back to the main front harness is red. I ran a large ga. red wire to the positive battery cable. The horn relay works and I have two prongs on the plug that is on the end of the front light harness with power. When I ground the horn button the relay clicks and the voltage reg. is new and appears to work when I turn the key but I put another one on to be sure and that did not help. All switches are new, all cables are new and the engine starts.
Man, I thought once I got the engine running I would get to start on the bodywork but this electrical is kicking my a$$.
EB

Well, I found out that the new light switch I bought was not working.It was shorting out and blowing the fuse So I have a new one. I was only changing it because I have replaced everything else on this car. I installed the old one and now I have everything working in the light harness except the headlights. This may be the old switch causing that problem. I will install the new one this weekend and cross my fingers! Thanks for the help.
EB
Texas