Headlight switch dimmer question

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AuroraGirl

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The rheostat is on the hot side of the circuit, so the dash lights will remain grounded if the rheostat fails; they just wont receive power. The dome/courtesy circuit is the only lighting that uses ground to complete the circuits (dome and courtesy light are both on different circuits. The headlight switch must be grounded to turn on those lights (it grounds through the dash when mounted).

I do have wiring diagrams, but not of them are digitized or scanner friendly. Pretty much any instrument panel wiring diagram for any year of these trucks will work, as the basic wiring stayed the same.

I take it you have head, tail, and dome/courtesy, but no dash lights?
WOuld a poor ground to the switch cause the floor lamp to change brightness when a door is opened vs the switch is turned? SOUnds strange but its brighter on switch vs door.
 

AuroraGirl

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Lol it took me to read what I wrote here to follow my steps I realized I forgot to plug the intermediate harness into the rear circuit after I was probing around earlier today. I now have cluster and rear tail lights/side running working lights in front parking lights come on everything works except for when I hit the turn signal it goes into hazard mode where they all blink. Come on fellas someone must have gone thru this or have an idea I'm so close! I'm going to see about testing the flasher module tomorrow. If my horn isn't hooked up could that be a problem with this turn signal flasher mode? Does the turn signal cam get ground from the horn circuit?

I'm Also interested in some led bulbs for my dash since a few are out.
If you get LEDs make sure they are dimmable people often buy 194s or whatever (168? I dont remember) and they will be the non dimmable type. also getting cheap ones will show over time if not right away, quality LEDs will do you very well. if it has a plastic cover over hte chips, it will probably disperse better as well. if you find the cost to be too much right now, you could either do partial and light up the important spots or test it out first. If they all go LED, there is a chance(Esp with cheap ones) the brightness will be finnicky but with at least 1 halogen they may work normal and fine. Quality LEDs shouldnt have that issue tho
Some before and after.. I know dielectric grease is normally a good thing but in this case it's rock hard and it's covering any clean contact these post I don't think it's a good thing so I got it out of there.
mine looked about like that before.. maybe worse. i dont know what it was, it seemed a petroleum grease of some kind that got dusty and old.... definitely crispened things up when i fixed that.
 

AuroraGirl

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The wiring diagram for my '75 truck shows an 18 gauge black ground wire at the taillight,. However, IIRC it also has a rear ground wire in the middle of the harness up about behind the license plate area. Its a fairly large gauge white wire. I have the Camper Special package, but I think all that camper wiring connects up in the front, so I think the white ground wire is stock.
I wonder if that was cut in the later years, my truck doesnt seem to have that and the harness I fixed didnt have any extra white I dont think, but I do believe the trailer plug I decided to splice in I decided to ground to the area but it may have a harness spot also white? (I think 4 way flat ground is white, i could be misremembering)
 

Ellie Niner

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WOuld a poor ground to the switch cause the floor lamp to change brightness when a door is opened vs the switch is turned? SOUnds strange but its brighter on switch vs door.
Yes. I've had driver's door switches get garbaged up on both of my trucks, and in both cases, the dome/courtesy/cargo light would either come on dimmer than normal or not come on at all when the driver's door was opened. Either turning the headlight switch or opening the passenger side door made the dome light brighter. I usually get lazy and spray electrical contact cleaner into the switch and rotate the plunger back and forth a few times... and it usually works. When everything is functioning normally, it seems like the dome light gets a tiny bit brighter when you open a door vs the headlight switch.
 

AuroraGirl

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Yes. I've had driver's door switches get garbaged up on both of my trucks, and in both cases, the dome/courtesy/cargo light would either come on dimmer than normal or not come on at all when the driver's door was opened. Either turning the headlight switch or opening the passenger side door made the dome light brighter. I usually get lazy and spray electrical contact cleaner into the switch and rotate the plunger back and forth a few times... and it usually works. When everything is functioning normally, it seems like the dome light gets a tiny bit brighter when you open a door vs the headlight switch.
Oh okay, since I can see my door jamb switch from the ground under the cab and its not even pinned against the door on the driver door I will chalk that up to not gonna work for a while Lollll. I was considering getting another and moving it to a spot that is still.... not rusted out, because the driver door not turning it on sucks. Pass will, switch will. But the switch also turns on the heater control light and that is currently has an LED and just hangs in the dash board and usually blinds me. I would be wise to buy a new heater thing and reattach cables after unseizing em and stuff.. but considering it only has to ever be on or off and the fan switch and the on-off switch I wired into the power wire handle heat and the cables just stay in hot and defrost. well, the defrost one is seized but the hot-not cable works :O LOL

If the wires are long enough I should reroute or maybe just put the door jamb on a rocker and that way I can leave the door open without worry since I have to do the Lift and sometimes flip the door latch down because it flips up and then bashes into the striker. Poor cab :(
 

Ellie Niner

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Oh okay, since I can see my door jamb switch from the ground under the cab and its not even pinned against the door on the driver door I will chalk that up to not gonna work for a while Lollll. I was considering getting another and moving it to a spot that is still.... not rusted out, because the driver door not turning it on sucks. Pass will, switch will. But the switch also turns on the heater control light and that is currently has an LED and just hangs in the dash board and usually blinds me. I would be wise to buy a new heater thing and reattach cables after unseizing em and stuff.. but considering it only has to ever be on or off and the fan switch and the on-off switch I wired into the power wire handle heat and the cables just stay in hot and defrost. well, the defrost one is seized but the hot-not cable works :O LOL

If the wires are long enough I should reroute or maybe just put the door jamb on a rocker and that way I can leave the door open without worry since I have to do the Lift and sometimes flip the door latch down because it flips up and then bashes into the striker. Poor cab :(
Sounds sorta like my 1975. The left bedside flaps in the breeze when you're driving, and you could probably rip the driver's door off if you got mad enough, as the front pillar is pretty rotten. One thing I'm glad for is that I no longer live in a place where the roads are salted.

Still longing for snow, just not the nasty deicer the local gubmints love so dearly.
 

AuroraGirl

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I live in wisconsin and somehow SOMEHOW we have to use salt and **** and that rots our stuff, but somehow a state with wide open plains and just as much snow and cold weather, north dakota, does not have the same degree of rot and I would say that is probably because of the sanding is more prevalent instead of salt and back in my youth(most would say im still youth but circa 2009) I dont seem to remember any issues with sand nearly the same as salt does and they got around just fine including my dad when i would visit him. We have a good amount of north dakotans here they may have more to say lol but Not on the salted roads of wisconsin, but literally eating dirt for prob 15 years,
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I found these by stepping on the one and the ground bowed down and popped back up when i got off the spot. I dug with my shoe and found what I thought was a fender. I dig with a shovel and I Find two bedsides, not in great shape, but considering they were one with the mossy muddy ground for literally most of my life, some how they are both useable and mostly cosmeticly rusted.

Hugging dirt and worms and moisture vs being on salted roads is insane how much eating happens. I suppose the factory coatings and steel quality holdup to simple dirt and moisture more than corrosive and abrasive water loving salt which also crams itself wherever it can fit as snow or water dilted and then the money process starts.
 

AuroraGirl

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Sounds sorta like my 1975. The left bedside flaps in the breeze when you're driving, and you could probably rip the driver's door off if you got mad enough, as the front pillar is pretty rotten. One thing I'm glad for is that I no longer live in a place where the roads are salted.

Still longing for snow, just not the nasty deicer the local gubmints love so dearly.
I remember when my dads 75 k25, which came from montana originally, looked like a farm truck with some rust around the edges here and there but had a bed, fenders, etc... lol. it was also nice jet black still with scuffs here and there.

And it didnt take long in wisconsin for the bed to become a rotten tin can and that got peeled off for a dump bed. But the truck, frankly, has had a simple easy life here in terms of miles and use in the winter... and its got about the same amoutn of cab daamage as my square but located more to the foot area and straight over while mine is right along the bottom front to back creeps up to reveal the gas tank and stuff. So basically turned. He has worse front fenders but we have had replacement fenders since before i was born, my gpa brought them with from montana even. something about a recall or a class action and they were provided. Primed not painted. Frames are actually doing okay rust wise both of ours. BUt its just insane how much wisconsin has eaten that truck because I remember when it was grandpas plow truck and it resembled a nice simple jet black long bed 3/4 ton and had a yellow plow on the front and now its faded to hell rusty fenders has a aluminum and sheet metal riveted in place patchwork of floor and no bed lol. Gas tank is spot less tho! Figure that..
 

squarelyfe

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Hazards working? But turnsignal ain’t and the dash’s turn signal indicators are coming on at the same time / or staying on? Sounds like you should first make sure your lamp sockets aren’t also covered in dry n caked up grease. Distilled vinegar goes right thru all the grease ya can’t pick out with a toothpick, check your bulbs and make sure you’re using the right ones lol.
I replaced the sockets a couple of years ago, they are definitely clean. They function bright so I can't see it being a contact issue.
 

squarelyfe

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Either something is crossing on the back of the panel, the wiring from the panel to turn signal wiring or gotta be the switch itself. I did replace the switch a few yrs ago, but have been in there looking at my horn. The schematic looks to show one of the front lighting circuits is also sharing with horn? I was wondering since my horn isn't hooked up does that have anything to do with it.
 

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John Nes

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Well, your horn has nothing to do with this. And that black (horn) wire runs straight to the horn relay connector.

I’ve tried going back and reading what the problems were but it seems like there’s an evolving list of issues. And at this point can’t tell what the current issue your having is lol.


Did see you mention your sockets are new and “clean” but are all your parking lamp bulbs good?
 

squarelyfe

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Well, your horn has nothing to do with this. And that black (horn) wire runs straight to the horn relay connector.

I’ve tried going back and reading what the problems were but it seems like there’s an evolving list of issues. And at this point can’t tell what the current issue your having is lol.


Did see you mention your sockets are new and “clean” but are all your parking lamp bulbs good?
There is only one thing wrong I've fixed the others. Bulbs are correct and newer. The rear circuit operates as it's supposed to left and right turn signals break etc in the front when I signal it signals both sides as if it's in hazard mode. It's between the panel and the switch I just haven't had a chance to get back into it. Trying to decide whether I want to unrap and wrap back up an eighth of a mile of electrical tape off of the connection from the panel to the switch or disassemble the rest of my steering column to get to the switch pull it out and look closer at the wire that's inside. Both are a pain in the ass but that turn signal switch is newer so I don't know on the fence I may just order a new switch for the hell of it since I can get one for 20 bucks.
 
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Goldie Driver

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There is only one thing wrong I've fixed the others. Bulbs are correct and newer. The rear circuit operates as it's supposed to left and right turn signals break etc in the front when I signal it signals both sides as if it's in hazard mode. It's between the panel and the switch I just haven't had a chance to get back into it. Trying to decide whether I want to unrap and wrap back up an eighth of a mile of electrical tape off of the connection from the panel to the switch or disassemble the rest of my steering column to get to the switch pull it out and look closer at the wire that's inside. Both are a pain in the ass but that turn signal switch is newer so I don't know on the fence I may just order a new switch for the hell of it since I can get one for 20 bucks.

If you buy a new turn signal switch, plug it in to harness connector BEFORE you tear the column apart.

Save yourself a lot of time and hassle.

If it doesn't fix anything, why tear into the column?

Also, tie a string or wire to the connector of the old switch so you can pull that thru the column and then tie it to the new switch.

You can then pull the new wiring down exactly the way the old was.

Did that with kite string when I did the Camaro wiper switch- works like a champ.
 

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squarelyfe

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The new switch had no effect, the same problem exists. This is really starting to upset me!
 

squarelyfe

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Made a firewall ground to frame and didn't fix it. How important is it for the park sockets to need to be tight against the frame I mean it's already grounded from the wire correct? No idea what happened but now I only have flashers
 
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