55.2-59 Headlight wiring help

[Missyblue]

Hey so finally getting some lights wired.....headlights work as they should but parking lights are weird....I am working an aftermarket harness and fusebox and have purchased new socket wiring for the parking lights.
1st they didn't turn on at all. Then we grounded the socket with a temporary wire to the battery and then they worked......now they work even with it removed....kinda weird......but my problem is when I use the turn signal.they both flash there's no independent. I checked my wiring and I have a left turn to the left side and a right tunr to the right side........realizing now I didn't double check my column wiring ??? Better do that....but i just copied the plug i cut off when i put the new plug in for the harness but now sure how i would have goofed that haha...But didn't know if anyone had any ideas....

Assuming they are just supposed to ground to the body since they don't have a ground wire but didn't know if anyone ever added one or needed to?

Then we went for our 1st voyage on the main road yay! And when we got back she wouldn't turn off and I panicked.....had no clue what to do haha.....the stupid aftermarket ignition had broken inside. Only been started like maybe 15 -20 times just crazy! So researching that as well.......I think it was a generic but dorman has one maybe they are better? I need this kind so it clamps itself.to the dash and then has the wiring studs on the back
https://shop.advanceautoparts.com/p/...E&gclsrc=aw.ds

Photos for fun...her 1st time.seeing the road and lights on!!

[leegreen]

I would run grounds to each light socket. They didn't work without a ground, now the turn signals flash together. Sounds to me like one side does not have a ground and is reaching ground through the park light filament in one bulb to the other side. I'd ground the rear lights as well.

[joedoh]

read the instructions for your wiring harness to column wiring very carefully, you will see there are two ways to wire the brake/turn at the column, you want to use the way that uses a single brake/turn bulb. if you wire it as the separate brake turn bulb it will work the way you are describing, both sides flashing.


I have helped a lot of guys with their trucks and when they have this problem, this is the reason 95% of the time. last 5% time it wasnt that way was when there was a short in the socket.

[dsraven]

yup, sounds like a ground problem. to be sure, remove the bulbs front and rear, then turn on the park lights and see which wire is hot at each socket. be carefull not to ground the test light or a fuse will (should) blow. I usually get around this by simply putting a straw or piece of vacuum hose over the test light so only the end of the tester is visible. label those wires. then turn the park lights off and turn on the signals, key likely needs to be on. sometimes I simply turn on the 4 way flashers as they use the same wire and the key doesn't need to be on-especially if you are running the old points ignition system. test the sockets for that all around and label. it may not flash because there is no bulb for resistance but it should power on that circuit. label those wires. now jamb something on the brake pedal so the brake lights will activate and test the sockets for that. it should only light up the rear sockets and should be the same wire as the 4 ways and signals.
once you get the wires in the right places for each light, so the signals and brakes light up the bright element on the bulb, then ensure each socket also has a ground wire that goes to, usually, a body panel. then make sure that body panel is also grounded. sometimes the wire looks excellently connected to the body panel but the panel itself isn't connected to a ground because of fresh paint or whatever. for the front lights the ground may be to the rad support but then the rad support isn't grounded. I usually run a ground cable from the battery to the frame and another to the engine. then smaller wires to each body panel that is used for a ground and also to the cab. bare metal, star washer, some sort of anti corrosion over that when done.
if you run led bulbs your system may need some tweaking because they don't draw much so an electronic flasher unit may be required. also, they are polarity sensitive so they need to be wired correctly and will need a good ground and clean connections inside the bulb sockets etc.

[dsraven]

joedoh makes an excellent point again on the wiring at the column. some signal switches were made for a seperate turn signal bulb out back. if unsure do the tests at the column connection. sometimes a paper clip or one of those "t" pins will push into the plug while connected. I use those all the time when testing circuits.
https://www.walmart.ca/en/ip/T-Pins-...E&gclsrc=aw.ds

[mr48chev]

A few questions:

What wiring kit? Brand and part number.

What headlight switch are you using?
Remember that stock TF park light switches only have the front park lights on when the switch is in "park" They don't work when the headlights are on unless you move the front park light wire.

I'm with the group that says bad grounds. All of that nice paint on different panels is great electrical insulation. Ground wires from the sockets to good clean grounds are your best bet.

On the ignition switch, My luck has never been good with a universal aftermarket ignition switch in an AD or a TF. They just flat come loose in the hole and make a mess no matter what you do. I'd go for a good quality oem style replacement switch.

They aren't inexpensive but you will be happier in the long run.

https://www.classicparts.com/1955-56...ctinfo/53-411/

[_Ogre]

Originally Posted by mr48chev

What headlight switch are you using?
Remember that stock TF park light switches only have the front park lights on when the switch is in "park" They don't work when the headlights are on unless you move the front park light wire.

Yes. This is correct and first thing I thought about when you had headlights and parking light on at the same time. Something is not wired right at the switch.

You probably have a ground issue. Make sure you have as heavy ground cable To the block, as the power cable to starter. Then a heavy ground cable to the frame and to the body from the block. My TRUK doesn't have individual ground wires to each socket, not needed until your vehicle gets rusty and crusty and by then the additional ground wires will need replacing. TRUK has run fine for 12 years.

Look at joedoe's suggestions. Unless you added extra light fixtures, like the one ton trucks had, you have double filament bulbs back for tail and stop/turn and up front for running and turn.

[mr48chev]

With a stock switch most guys move the front park light wire to the tail light connection on the switch to have park lights on the front when the headlights are on.

Here's Blacksheep's post on an older thread plus here is the link to that thread http://67-72chevytrucks.com/vboard/s...d.php?t=550576

[Missyblue]

Originally Posted by leegreen

I would run grounds to each light socket. They didn't work without a ground, now the turn signals flash together. Sounds to me like one side does not have a ground and is reaching ground through the park light filament in one bulb to the other side. I'd ground the rear lights as well.

So my rear we sanded well and replaced the mount before they finally grounded themselves. Are you saying you would add a ground wire from them to the frame or bedside?

[Missyblue]

Originally Posted by joedoh

read the instructions for your wiring harness to column wiring very carefully, you will see there are two ways to wire the brake/turn at the column, you want to use the way that uses a single brake/turn bulb. if you wire it as the separate brake turn bulb it will work the way you are describing, both sides flashing.


I have helped a lot of guys with their trucks and when they have this problem, this is the reason 95% of the time. last 5% time it wasnt that way was when there was a short in the socket.

Thank you. I will have to read again. My wiring harness instructions seemed to match the exact wiring of the plug..I'll try to attach. It seems to make poor quality on attaching. I'm using this speedway kit
https://www.google.com/search?q=spee...obile&ie=UTF-8

[Missyblue]

Originally Posted by dsraven

ensure each socket also has a ground wire that goes to, usually, a body panel. then make sure that body panel is also grounded. sometimes the wire looks excellently connected to the body panel but the panel itself isn't connected to a ground because of fresh paint or whatever. for the front lights the ground may be to the rad support but then the rad support isn't grounded. I usually run a ground cable from the battery to the frame and another to the engine. then smaller wires to each body panel that is used for a ground and also to the cab. bare metal, star washer, some sort of anti corrosion over that when done.
if you run led bulbs your system may need some tweaking because they don't draw much so an electronic flasher unit may be required. also, they are polarity sensitive so they need to be wired correctly and will need a good ground and clean connections inside the bulb sockets etc.

I have the battery and body grounded well, to the firewall also....but not to body panels up front.... We also added a frame to bed ground. The front headlights I made sure to sand off paint before installing the ground wire for each. But the parking lights are just grounded by contact mounting. Dad was thinking maybe add a ground wire for them also?? The rear lights are led and we had to replace the br a ckets and sand the paint before they finally grounded themselves.

[Missyblue]

[quote=mr48chev;9160599] few questions:

What wiring kit? Brand and part number.[/QUOTE
https://www.speedwaymotors.com/22-Ci...BoCQM8QAvD_BwE

Originally Posted by mr48chev

what headlight switch are you using?

Remember that stock TF park light switches only have the front park lights on when the switch is in "park" They don't work when the headlights are on unless you move the front park light wire.

I'm with the group that says bad grounds. All of that nice paint on different panels is great electrical insulation. Ground wires from the sockets to good clean grounds are your best bet.

On the ignition switch, My luck has never been good with a universal aftermarket ignition switch in an AD or a TF. They just flat come loose in the hole and make a mess no matter what you do. I'd go for a good quality oem style replacement switch.

They aren't inexpensive but you will be happier in the long run.

https://www.classicparts.com/1955-56...ctinfo/53-411/

The headlight switch came with it. Seems the instructions say it is made to make the parking lights be on with the headlights...

And I can't remember why we didn't get an original ignition switch......been too long....would it have something to do with the fact that I'm using a computer from a 1992 chevy?? I need to research and try to remember....might have just been my Mechanic helper sourced something local to not wait....

[Missyblue]

Originally Posted by _Ogre

Yes. This is correct and first thing I thought about when you had headlights and parking light on at the same time. Something is not wired right at the switch.

You probably have a ground issue. Make sure you have as heavy ground cable To the block, as the power cable to starter. Then a heavy ground cable to the frame and to the body from the block. My TRUK doesn't have individual ground wires to each socket, not needed until your vehicle gets rusty and crusty and by then the additional ground wires will need replacing. TRUK has run fine for 12 years.

Look at joedoe's suggestions. Unless you added extra light fixtures, like the one ton trucks had, you have double filament bulbs back for tail and stop/turn and up front for running and turn.

OK yeah so we tested the bulbs and matched the wiring for the double filament bulb....like dim for running light and bright side for turn etc....the wiring kit has a left and right wire for the turn so just not sure where things are going weird. Have to go investigate the wolumb but I wired it per the instructions I attached before from the speedeway kit.....
Did you have to grind down your pretty paint for the mounting locations? My paint isn't pretty but just wondering haha

[leegreen]

<Are you saying you would add a ground wire from them to the frame or bedside?>

What I did for my own truck for grounds:
battery to block, block to frame, block to body
block to body goes to a bolt on firewall that goes through a sanded hole with star washer through firewall and provides an accessible ground point both inside and outside the cab.
From that ground point I have a ground wire run to rad support to another bolt. Each headlight and park/turn has a ground wire to that bolt. I soldered a ground wire to the bulb holder in each park light. Similar ground point and wires in rear.
All wires are soldered to the crimps and heat shrunk (some people will refute soldering connections as creating a stress point that will fail that but I have never had a wire I soldered fail).
All ground bolts / connections outside the cab have a coating of conductive grease.

This is overkill, but I have seen a lot of mystery electrical gremlins that were resolved by fixing ground issues, usually corroded connections.


The ignitions switch you show in post 12 looks like a GM column mount style, not a TF replacement dash switch. So I guess you have a newer column.

[Missyblue]

Originally Posted by leegreen

<Are you saying you would add a ground wire from them to the frame or bedside?>

What I did for my own truck for grounds:
battery to block, block to frame, block to body
block to body goes to a bolt on firewall that goes through a sanded hole with star washer through firewall and provides an accessible ground point both inside and outside the cab.
From that ground point I have a ground wire run to rad support to another bolt. Each headlight and park/turn has a ground wire to that bolt. I soldered a ground wire to the bulb holder in each park light. Similar ground point and wires in rear.
All wires are soldered to the crimps and heat shrunk (some people will refute soldering connections as creating a stress point that will fail that but I have never had a wire I soldered fail).
All ground bolts / connections outside the cab have a coating of conductive grease.

This is overkill, but I have seen a lot of mystery electrical gremlins that were resolved by fixing ground issues, usually corroded connections.


The ignitions switch you show in post 12 looks like a GM column mount style, not a TF replacement dash switch. So I guess you have a newer column.

Thank you for the info! So I think I have all your grounds except e haven't grounded the radiator support or the park lights.....my dad wired his semi years back so has been pretty vocal about me making sure I grind off paint and install my grounds to bare metal. But I didn't do anything to the paint when mounting the eyebrows with the parking lights as he wasn't there and I wasn't thinking. Could I attach just like a sheet metal screw or small bolt and make a hole.in the little square housing that holds the parking light if I did it? He's not the soldering type but I do have the tool.

And yes I am using a 70s gm van column as my original was for a manual and we have an automatic now.
And In the middle of the night I remembered why I can't use the original starter switch.....one of those we changed one thing and it changes 50 others......we went to power disk brakes and the frame mount booster wouldn't fit due to my larger 4l80e transmission so we had to go firewall mount and the brake pedal and booster have a bolt that is right behind the ignition. The original with its plug is too long to fit so the aftermarket plug was stubbier and worked because of how it is wired.

[dsraven]

sounds like you have a ground issue on the front lights. if you have a couple of jumper wires, like a test wire with alligator clips, try using them from a good ground to the light housings and see if the problem goes away. I have a cheap old light duty set of booster cables that I found in a wreck, with cheap clamps that don't have much squeeze pressure, and they have come in handy for such things. they have a larger clamp so they stay attached to things like light sockets but they don't squeeze so hard they crush the light socket. if you don't have any test leads that will work just use some mechanics wire, fence wire or whatever you have laying around, it doesn't need to be insulated as it is a ground wire so unless it touches something that is battery positive you'll be fine. vice grip it to the frame, run it under the truck where there is no battery positive to short out and then touch that to the light sockets with the signals on. maybe you find your problem.
since the GMC mustache signal light housings are screwed to the mustache, and the mustache is screwed to the fenders and other grille parts, and they are also screwed to the rad support, etc, there are many spots that there could be a bad ground. that is why I suggest to run a dedicated ground wire to the light and eliminate all the other possible bad connections. like LG says, solder a wire to the light socket and then ground that wire to a good clean spot on the frame, with a star washer, and when you are certain it is all good coat the connections with some grease or at least shoot some spray bomb paint over it. done.
https://www.grote.com/electrical-con...alant/99170-1/

[_Ogre]

Star washers and conductive grease or at least anti corrosive grease might help. I use a copper conductive grease on my grounds My tail end is different than most, my taillights are 2 wire led that ground to my frame.