jread199

I am putting my 1967 olds cutlass back together, and despite checking every wire before reassembly i am having some electrical issues.;
issue#1 the fuse box seems to loose connection with the fusses on the circut of courtesy lighting and tail lights/ip lights, if i scratch the draw side of fuse with a screwdriver I can see a faint spark and the circut comes to life and then for no reason at all the circut would go dead again never blowing the 20 amp fuse. I cleaned the socket where the fuse goes put spray on copper on the fuse same result the connection on the right side of the fuse is solid.
Issue #2 the brake lights on the right side of the car will not come on. There is continuity in the tail lamp harness as well as the harness that runs in the conduit inside the car. the flashers are all functioning properly as a matter of fact when the flashers are on the right side tail light blink which i do not believe is correct. I don't know if there is a problem with the hazard switch, looking at the service manual the right side brake light runs through the switch as well as the left side but I could not trace it (the left one)
I tried to be extremely thorough with the old wiring checking, unwraping every harness checking all connections fixing bad ones (properly with solder and shrink tube) to avoid these problems hoping someone can lead me in the right direction thanks in advance John Read Smyrna De.

oldcutlass

First you need to get your contact problem fixed at the fuse holders. Then work on one circuit at a time until you have everything clean and tight. The spring loaded tail lamp sockets are notorious for loose connections. The wires are usually hard and brittle so be careful.

BILL DEMMER

just for laughs, replace the fuse on the circuit that is giving you problems.
the tubular fuses can break internally, over time. they can look good and test good, but be intermittent.

x2 on the spring terminals at the bulb sockets.


bill

Oldsguy

A good ground is necessary for every circuit to work well. We often only pay attention to the + side (battery voltage). Especially for circuits in trim lights and such like you are having difficulty with a ground can be overlooked. Sometimes with the interior and upholstery a separate ground wire is used. Try using a long wire as a temporary ground from whatever light doesn't work. Touch the ground side of the lamp to a known good ground on the frame or better yet the engine or better yet the battery ground post. Just touch it and if you get a light then you have a poor ground on that circuit but remember lights have switches too so they may be your culprit. Some circuits like the courtesy lights activated by the doors opening are like that, the switch interrupts the ground (actually they are physically in the door post so they are grounded). When the door opens the switch makes contact and completes the ground for the light to illuminate.

jread199

Thank you very much for the replies! I found a you tube video last night (motor age.com) that talked specifically about voltage drop in an electrical system and found the information pertinent, because voltage at the brake lamp was 7.62 volts which according to what i have learned means something is stealing the remaining 5 volts from the rh side brake light circut; I have done research on how to use my multimeter to measure draw so hopefully may have more luck finding the culprit. as far as the sockets of all the lamps I figured out how to fix them by either manipulating the metal bend or replacing the internal springs that do not expand like they should, The fuses are new I may try an electrical cleaner and dielectric grease. but who knows maybe i will find another problem that is causing that situation. thanks again for the help, always grateful for those you take time to help!

joe_padavano

If you see a spark then quickly blow the fuse when you are installing a new fuse, that means there is a short to ground somewhere in the circuit downstream from the fuse. You'll need to trace the wire harness to find it.

oldcutlass

It is a mechanical connection problem.

jread199

I set out today to fix the electrical problem taking all day if need be. first I took off the steering wheel and connected the turn signal lever( it was off because it just got in the way and the steering wheel was on just to move it in and out of the garage at this time) turns out the turn signal cam was not exactly in the middle and for some reason affected the right brake lights, new plastic switch should fix that problem. Took the fuse panel out, used a dremel with a small wire wheel and cleaned the contacts. then brushed flux on the spring connectors and burned it off with a soldering iron, turned the fuse panel around and put a small dab of solder where wire is crimped on the terminal, and that seemed to fix the connection problem in the fuse box and hopefully fixed forever, thanks for the suggestions much appreciated!