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OK, let me describe the problem in detail:

Since I first got the car, the turn signals would work, but when viewed from behind, the left turn signal would blink, but the right tail light would also dimly blink as well. The right turn signal works perfectly, just to let you know.

Now, if I turn on either the parking lights or the headlights on, the left turn signals front and rear will come on, but not blink. The right turn signal is not affected and will still work perfectly. Turn the lights off, and it works as described above.

OK, I replaced the head light switch and now my dash lights work, well half of them do from the fuel gauge to around the 40 to 50 MPH mark. Yay!

But, now that they work, I noticed that the dash lights will not only come on when I hit the breaks, but when I use the left turn signal as well. Using the right turn signal will not do this, it seems to work without issue.

WTF is up with this car?!
 

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In a general sense, lights that dimly flash with other lights is a poor grounding issue. The power is trying to complete the circuit, but with a bad ground, it goes through another bulb instead to get there. If it's bad enough, you can have lights go from off to full on. However, your second issue sounds more like a turn signal switch problem.

One thing at a time - get your manual and check/clean/tighten every ground in the book. Don't just look for them, as you will never find them all. See what improves and go from there. Most electrical issues on old cars begin with poor grounds.

David
 

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When it gets snarled up like that you could use a 1965 Ford Galaxie Wiring Diagram Manual. A Jim Osborne Reproductions, book # MP 135. Twenty eight pages of wiring and it was pretty cheap, like $10.

It will help you more than I could!
 

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had similar issues with my 65, turned out it was ground issues at the tail lights. Made new grounds on both rear tails and fixed it right up. gas gauge was jsut a little sticky on mine. removed mine, cleaned it up and it has been working fine.. I think it was a little varnished from sitting 9 years at 1/4 full. fortunate for me the tank wasnt rusted up inside.
 

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You know there are around 24 item that take a ground. Once you check the body ground to battery is good,go to truck and check the grounds. Check the license plate light ground,tail light ground. The red-black wire is you tail light and back up light ground. Now up front And check the head light and park light ground. Black wire. Allso check your gas tank sending unit ground. The dash ground, you really don't have a problem with. Your problem is ground.
 

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Say there is a ground wire to a screw in the frame, how do you check it?Also, are some of the grounds just where the housing is in the sheet metal? How do you check those?
 

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I am getting lost between questions.

The battery ground should go from the battery to the front or side of the engine block. On the back of the block there should be a ground strap (braided) that conncets to the firewall. This provides the ground for all the lights and instruments, if you don't have one, GET ONE. I have seen people run the ground from the block to the frame, wrong. Nothing should get it's ground from the frame. There are rubber body bushings between the frame and body which could isolate the ground from the frame and body - although the bolts usually provide the continuity between them. Problem is once they bolts start rusting the ground continuity gets less and less, sometimes causing problems like are being discussed.

On later models like my 67 there are multi-wire plug in connectors on the engine side of the firewall for lights, horn, engine and other electrical stuff coming from the light switch and ignition switch. I have heard of corrosion getting built up in the plugs, so people are suggesting you check those to see that they are clean. That could be it, but those plugs only carry positive current and do not provide ground.
 

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Just undo those ground screws, sand the metal around the screw hole , the actual wire end loop itself too, do tailight grounds 1st, license plate ground & work forward. Headlight ground screws same deal
The 2 plugs at the firewall, on Dr.side just inside the hood hinge, they unplug from the firewall, engine side. See those little silver end plugs? Are they green with corrosion? clean em up & plug em back in.
 

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Just undo those ground screws, sand the metal around the screw hole , the actual wire end loop itself too, do tailight grounds 1st, license plate ground & work forward. Headlight ground screws same deal
The 2 plugs at the firewall, on Dr.side just inside the hood hinge, they unplug from the firewall, engine side. See those little silver end plugs? Are they green with corrosion? clean em up & plug em back in.

Yeah that is what I was wondering, was there a realistic way to "check" all the grounds. So I guess the answer is no? Just clean them up and hope for the best?
 

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Yeah that is what I was wondering, was there a realistic way to "check" all the grounds. So I guess the answer is no? Just clean them up and hope for the best?
You can test wiring and connections with an ohm meter or volt meter (VOM or DMM). However, for grounding issues, by the time you test each one, you could be done cleaning them. Since cleaning is usually needed, you might as well go that route, or you'll be chasing ghosts one day anyway. If you are still having issues, then you can take the time to pull the meter out, but at least you'll know you won't be getting any weirdness from a crappy ground at the front of the car or under the dash affecting an issue at the rear - which they can do.

David
 

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OOH OOH OOH - I think Ive seen this before :)

check your left rear turn signal bulb...should be a 1157, if someone stuck a single filament bulb in that socket, it shorts the brake/turn filaments together, brakes backfeed everything else.

my brother had a dodge van with this issue back in high school, took a bit of head scratching to figure it out. a melted damaged socket could do it, but I know the wrong bulb will too

Tim
 

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OOH OOH OOH - I think Ive seen this before :)

check your left rear turn signal bulb...should be a 1157, if someone stuck a single filament bulb in that socket, it shorts the brake/turn filaments together, brakes backfeed everything else.

my brother had a dodge van with this issue back in high school, took a bit of head scratching to figure it out. a melted damaged socket could do it, but I know the wrong bulb will too

Tim
Wow.... That sounds like a winner to me, I would check that first for sure.

The door lights in my LTD actually are a double pin bulb and when I got the car it would blow the fuse when the doors were open. When I had the dash apart this summer I decided to figure that issue out, and in my luck started on the drivers side and traced all the wiring around to the passenger door and couldn't figure it out. Turns out someone put a single contact bulb in the passenger door at some point so the 12v and ground contact were connected by the base of the bulb and blew the fuse when either door was opened.

I could see how with the tail-lights the base being the ground, a single pin would allow the voltage to back feed causing all sorts of issues. Good catch!
 

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Discussion Starter #15
OOH OOH OOH - I think Ive seen this before :)

check your left rear turn signal bulb...should be a 1157, if someone stuck a single filament bulb in that socket, it shorts the brake/turn filaments together, brakes backfeed everything else.

my brother had a dodge van with this issue back in high school, took a bit of head scratching to figure it out. a melted damaged socket could do it, but I know the wrong bulb will too

Tim
LMAO...I come back into this thread to post an update and here I see this post. Yep, when I pulled that bulb out, the issues stopped, I replaced the bulb, and BAM! problem solved. :D
 

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Awesome! That's the cool little experiences part that make this forum primo. Excellent.

David
 
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