Lights are all wonky

[plummrey]

1984 C10 just got it in Dec and finding stuff. With my lights on for night time: there's no dash lights, left taillight light doesn’t work (not sure for breaks last time I check they did)

With my lights off:
put left turn signal on and front is fine, large taillight blinking but not the smaller one, the opposite small light blinks
Put right turn signal on and same as above

Same with the two marker lights in the front an opposite will work

Last time I checked the reverse did work same for brake lights. No interior light or cargo light works, all those cables are fine because I just redid the flooring

I’m not really familiar with wiring unless it’s the basic hooking up speakers or color to color wiring etc

Where should I start

 

[plummrey]

I also checked the gauge cluster circuit board and there’s no burn outs or breaks, replaced bulbs though

 

[SirRobyn0]

1984 C10 just got it in Dec and finding stuff. With my lights on for night time: there's no dash lights, left taillight light doesn’t work (not sure for breaks last time I check they did)

With my lights off:
put left turn signal on and front is fine, large taillight blinking but not the smaller one, the opposite small light blinks
Put right turn signal on and same as above

Same with the two marker lights in the front an opposite will work

Last time I checked the reverse did work same for brake lights. No interior light or cargo light works, all those cables are fine because I just redid the flooring

I’m not really familiar with wiring unless it’s the basic hooking up speakers or color to color wiring etc

Where should I start

Ok I'm going to quote you and answer below in italics.

"there's no dash lights, left taillight light doesn’t work (not sure for breaks last time I check they did)"

Dash lights I "think" come right off the headlight switch, hopefully someone more knowledgeable will come along to help with that.

Left tail light. Take a test light back there and see if there is power to one of the terminal sockets with the headlights on, if so then take a close look at the socket and ground connection back there. I think the most common thing would be a burned out bulb, followed by a ground issue or socket.


"With my lights off:
put left turn signal on and front is fine, large taillight blinking but not the smaller one, the opposite small light blinks
Put right turn signal on and same as above"

I can't tell what your talking about there is no small blinking light on the rear just one bulb out back, so if your talking about the front the same thing applies, check for power with a test light, inspect the socket and check the ground. Hopefully this has helped.

 

[plummrey]

Thanks, I’ve been looking on here at other posts too and will check groundings, this pic attached is like the housing for my taillights, the left side, the top is running/brake/signal the bottom reverse and the smaller hole has the little bulb that signals with the regular bulb signal. It’s to the side so I’m guessing it’s so people can see the signal on the side since there’s no yellow maker lights on the side in the back like on older models, but my front has the yellow marker lights
I found some diagrams and someone else mentioned factory ground locations, hopefully I can come back here and say found the problem and it’s fixed

 

[SirRobyn0]

Thanks, I’ve been looking on here at other posts too and will check groundings, this pic attached is like the housing for my taillights, the left side, the top is running/brake/signal the bottom reverse and the smaller hole has the little bulb that signals with the regular bulb signal. It’s to the side so I’m guessing it’s so people can see the signal on the side since there’s no yellow maker lights on the side in the back like on older models, but my front has the yellow marker lights
I found some diagrams and someone else mentioned factory ground locations, hopefully I can come back here and say found the problem and it’s fixed

You'll get it fixed, what your doing is not likely hard, but it could be a bit time consuming depending on your skill level. Just remember to check for power, check the socket, check the ground.

That little bulb in the rear is a marker light it does not flash, just comes on with the running lights. I can double check that on my truck if you want.

 

[75gmck25]

You said you checked the instrument panel circuit board, so I guess you took the cluster out. Did you ensure the cluster ground was reconnected? It’s up under the dash and it will be either grounded to the parking brake mechanism or to a dedicated ground point up on the firewall. If disconnected it causes multiple weird lighting symptoms.

The lack of flashing for the front marker light is usually just due to a bad ground for the light housing. Clean up the eye in the end of the ground wire and send down to bare metal where it screw into the truck body. The other possibility is that a two terminal bulb (like the front park lights) is plugged into the socket in the wrong orientation.

 

[plummrey]

You'll get it fixed, what your doing is not likely hard, but it could be a bit time consuming depending on your skill level. Just remember to check for power, check the socket, check the ground.

That little bulb in the rear is a marker light it does not flash, just comes on with the running lights. I can double check that on my truck if you want.

Yes please see if you back marker lights blink with your signals

 

[plummrey]

You said you checked the instrument panel circuit board, so I guess you took the cluster out. Did you ensure the cluster ground was reconnected? It’s up under the dash and it will be either grounded to the parking brake mechanism or to a dedicated ground point up on the firewall. If disconnected it causes multiple weird lighting symptoms.

The lack of flashing for the front marker light is usually just due to a bad ground for the light housing. Clean up the eye in the end of the ground wire and send down to bare metal where it screw into the truck body. The other possibility is that a two terminal bulb (like the front park lights) is plugged into the socket in the wrong orientation.

I only saw the plug for the clock, the black cable (looks like cable tv cord), plug beside that and the large plug with all the cables, I will check the grounding as you said by the brake, been cleaning the grounds I see under the hood, haven’t hooked them back up yet though, will check taillight socket’s tomorrow if it’s not raining

 

[SirRobyn0]

Yes please see if you back marker lights blink with your signals

My truck is not with me at work so I will attempt to remember tonight.

 

[plummrey]

No worries, I cleaned the grounds I could find in the hood, I installed i new windshield wiper/signal switch stick, I couldn’t feed it through the column so I just have the cord on the outside plugged in, but now when I do any signals all the light flash except front left marker.

Also it will not go into gears, I’ve not messed with anything with the gears, the other day we tried cranking it and (wouldn’t crank) but heard something trying turn at our feet where transmission is , does that mean it’s locked up

 

[plummrey]

Scratch that about the gears it’s going in gears now

 

[SirRobyn0]

No worries, I cleaned the grounds I could find in the hood, I installed i new windshield wiper/signal switch stick, I couldn’t feed it through the column so I just have the cord on the outside plugged in, but now when I do any signals all the light flash except front left marker.

Also it will not go into gears, I’ve not messed with anything with the gears, the other day we tried cranking it and (wouldn’t crank) but heard something trying turn at our feet where transmission is , does that mean it’s locked up

Might just be that the battery is low on charge. Especially if you have been messing with the lights and haven't run the engine much. Maybe put it on a battery charger or if you don't have one try to jump it.

 

[plummrey]

I’m going to install led flasher since I read led bulbs won’t work right with the regular flasher relay,, but even before when bulbs were regular 1157s a couple did not work right. I did clean the sockets too today, tomorrow I’ll receive the flashers.

Also got a headlight switch on the way too in case I need to change that, dimmer didn’t work on cluster with regular tiny bulbs either

 

[Doppleganger]

Just curious......was there remnants of the ghost of trailer-hitch past on your truck? Seems thats when lights get wonky, or even worse, discombobulated.

 

[DoubleDingo]

Just curious......was there remnants of the ghost of trailer-hitch past on your truck? Seems thats when lights get wonky, or even worse, discombobulated.

Had that happen on my jeep, it came with a factory tow package, so it had the trailer light kit installed behind some paneling, and somebody went in and installed another one. It caused some headaches, luckily Pop knew where to check the wires going to the rear lights and spotted the extra trailer light kit, he then removed both of them and we wired everything back together and the problem was solved.