Electrical Gremlin

[suki243]

So, ever since i replaced my wiring all has been good, except 1 problem... it has to do with my turn signal/ brake lights.
Sometimes the left side doesn't work, the other time the right side doesn't work but the left side does. I thought i had fixed it hundreds of times, but the other day my parents said that my left side turn signal/ brake light don't work... I decided i'd check out the bulb, the bulb was burnt, totally black, i replaced it.
Then the turn signal and parking light worked again (btw the parking lights work on both sides always) but i could never really check the brake light because i can't sit and look at the same time.
So, my uncle came over the other day and i was moving the car and he said my brake light is out on the left side... i said thats impossible i just changed it the other day, i open it up the bulb is fine, i check the wire, no voltage is coming the left side... I ask my dad to step on the brake and they're right the left side is not lighting up. I decide to put it away for the night and check in the morning w/ the wiring schematics.
I then get a weight and put it on the brake pedal this time the left side works and the right side doesn't i check the voltage for my third brake light (not hooked up to a light yet) and it is receiving voltage I'm not sure where to go from here... Could it be a faulty turn signal steering column? right now it has the problem of when i turn the left signal on and turn the signal will cancel itself after the turn is complete, but not on the left side. (btw the turn signal and brake light are sending voltage from the same wire)

This is a EZ wiring mini 21 harness

 

[Tim65GT]

Sounds like a bad turn signal switch. Check the cancelling mechanism on the steering wheel. On the stock wheel, it's a ring with two nubs on it. If it's maladjusted, it could be touching causing your indication. On a aftermarket wheel, it could be anything, just make sure the cancelling mechanism is aligned correctly.

 

[suki243]

It's a stock one, I'll check it out tomorrow if i can.

 

[mustangman1974]

Make sure the grounds on the front parking lights are good. I chased that gremlin for a year before I noticed that the body shop didn't correctly installyt he front parking lights.

 

[suki243]

Hmm, but would that cause no voltage to go to the back-lights? The turn signal and parking lights would work but not the brake light .

 

[suki243]

Tim you were right, it's the Turn signal switch. Since mine doesn't cancel by itself sometimes it remains in whatever position it was before. E.g. if i had just taken a left and not fully turned off the signal it will cut power for the brake light on the left side. However, I don't have the socket big enough to open up the steering wheel nut in order to adjust the canceling mechanism. I'm going to have to either take it to my mechanic and have him open it and i'll adjust it from there, or go to my painter (who replaced my steering wheel ) and have him open it. Do you have any pics of what the canceling mechanism looks like and how to adjust it?

 

[68conv4sp]

I just replaced the turn signal/horn assembly on my 68. Not too bad a job. The toughest part was getting the wheel off. I had to use a puller to avoid damaging the bearing that holds the top of the shaft. I think the part was about $70 so if you're going to all the trouble to pull everythng apart, put in a new unit. And use dielectric grease in the horn contact rings on the bach side of your wheel.

Getting the wires pulled thry the column was not bad. There is a trick to getting the wires out of the plug so that it can be reused. Use a very small screw driver to push each locking tab back to allow each wire to be removed.

 

[Tim65GT]

suki243
Tim you were right, it's the Turn signal switch. Since mine doesn't cancel by itself sometimes it remains in whatever position it was before. E.g. if i had just taken a left and not fully turned off the signal it will cut power for the brake light on the left side. However, I don't have the socket big enough to open up the steering wheel nut in order to adjust the canceling mechanism. I'm going to have to either take it to my mechanic and have him open it and i'll adjust it from there, or go to my painter (who replaced my steering wheel ) and have him open it. Do you have any pics of what the canceling mechanism looks like and how to adjust it?

I have since switched to a '68 column which has an entire different switch.

Here is a pic of the back of my old steering wheel with the cancelling ring still attached. When facing the front of the wheel the two nubs are pointing to the left. (9:00 position) It's made of spring steel, so adjusting it is just a matter of rotating it with som pliers.

Don't forget, depth is important too. If it's too deep (toward the switch) it will contact other parts of the switch and cause problems. If it's not deep enough it won't contact the two canceling arms. Have you ever removed your column? It might be shifted foward or back a tad causing problems.

 

[suki243]

Thanks, I'm going bak to college for the week, next weekend i'll try and get the steering wheel off and let you know what I find.

I've never taken the steering column out, my painter put in a new steering wheel for me (it was a stock replacement) but thats about it. Not sue what the PO did though, if i look at the wires coming from the turn signal switch they look like they are new, they've still got color and are not corroded or hard.

 

[mustangman1974]

yeah the whole system grounds through the front turn signal lights. if the ground is crappy the somtimes the flasher will not work. anyhow if you replace the turn signal and it still gives you issues check that ground wire. HEHE I chased a similar problem for over a year.

 

[Rusty67]

I believe the socket you need is a 15/16" socket. If memory serves me thats what size the one on my 67 was. It can't be all that expensive to buy the socket you need.

You don't NEED a steering wheel puller. Just leave the nut threaded on how ever wide the nut is and yank at the correct angle. The wheel should break loose and the nut should stop the wheel from smacking you in the face. Remove the nut, remove the wheel.




I think my steering wheel is loose, can you tell me something about the nut behind the wheel ?

 

[soeasytobefake]

Parking lights

I have a 68 coupe and I've been working on getting all the lights operating properly. New headlights, parking lamp assembles, some of the wiring was shot.
Ive just recently got everything working and i noticed last night that when i turn on the headlights the parking lamps go out. I pull the dial out one click the lamps come on, and the rest of the way for the headlights, the lamps go back out.
The side markers stay on, as do the rear parking lamps, but the front turn/parking lamps shut right off. Ive read in some forums that this was normal for a 64 1/2 though 66, and some 67's.
I don't remember them operating that way before i started messing with the wiring under the dash. Anybody have any thoughts on that?

 

[Tim65GT]

soeasytobefake
Ive read in some forums that this was normal for a 64 1/2 though 66, and some 67's.

From the crapy '68 diagram i have, it looks like it also picks up the front park lamp power from it's own terminal on the headlamp switch, so I would think it's similar to the early Mustangs.

Maybe someone with a '68 could chime in.