Author Topic: Cab/Clearance Light wiring help  (Read 4572 times)

Offline SquareBody86

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Cab/Clearance Light wiring help
« on: April 15, 2016, 05:58:01 PM »
Right then, first off a bit of an introduction on my truck. It's a 1986 c10 Silverado, long box fleet side 305/700r4, 160,xxx miles second motor original trans ( the swap was done by the original owner, no idea if it's a 305 or what).

 I got her a few years back off the second owner for $600 as my first truck and have been working on it to get the old girl back on the road. She's a bit rough but seems fairly solid considering she's been a northeast Michigan truck all her life. So far I've put in a new driver side floor board from   truck, bit of trimming and a few self tapping screws worked wonders, new drivers side inner fender and hopefully I can get the second one in soon. Brakes have been gone through and the only thing that hasn't been replaced is the front rotors and the backing plates as the rotors seemed good for the time being. All new rear seals on the rear end, oil change & filter, basically the usual stuff you'd have to do after 30 years (she'll be 30 in june). I also did a few cosmetic things such as new headlight bezels and a nice set of horns and cab lights of which is the point of this little call for help here.

Earlier this week I finally got to getting the cab lights mounted, bit of work but they turned out great and with the horns have really given this old girl a new look. Now I'm not all that great when it comes to wiring, basics and thats it. for instance the little pump for the horns is wired right from the battery. positive runs from the battery to a toggle switch on the dash then to a push button then to the pump then the negative runs right back to the battery.

Well after testing out one of the lights (of which are LEDs) and finding out they're the full circuit style I figured heck and see if I could get them wired up so I spliced in a positive from the positive wire that's already coming off the battery for the horn and had it run to the inline fuse that came with the lights, then from there to the switch then from the switch up to the first light, then I had the negative of the first light go to the positive of the second and so on down to the of of which at the last light I had the negative run back down under the dash and spliced it into the negative for the little air pump.

I flipped the switch and nothing happened, I'm not sure if I wired it right or not as I really don't see anything anywhere on how to wire these up, help? (pics of the wiring soon as i can get them off my phone)

here's a few pics of the truck when we got her home, dad found out she can smoke the tires real good, well one at least, darn posi.

If it ain't broke don't fix it, upgrade it!

'Rusty' 1986 C10 Chevy Silverado, long box fleetside, LG4 305/TH700R4 with Edelbrock 1406, 2.73 rear ratio

Offline bd

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Re: Cab/Clearance Light wiring help
« Reply #1 on: April 15, 2016, 06:42:00 PM »
Welcome to the site.  Looks like you have quite a project going.

...Well after testing out one of the lights (of which are LEDs) and finding out they're the full circuit style....

What do you mean by, "full circuit style?"  Was this a kit with instructions or individual pieces that you wired together?

How many LEDs did you connect in series?  Any resistors or diodes involved? 

Pics would help.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline 1967KaiserM715

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Re: Cab/Clearance Light wiring help
« Reply #2 on: April 15, 2016, 09:08:20 PM »
Led lights are polarity sensitive( positive to positive, ground to ground) and tend to work best when wired parallel vs in a series(like you did) I'm not saying it won't work, but in series if one light fails, none work, also the voltage drop across the lights could cause the last few in line to not light(LEDs tend to be voltage sensitive)


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Current Vehicles:1985 GMC K10(Daily) 1991 GMC K2500(Daily) 1975 Beetle(not running) 1985 Mercedes 300D(not running) 1952 M35    1967 M715(not running)
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Offline LTZ C20

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Re: Cab/Clearance Light wiring help
« Reply #3 on: April 15, 2016, 09:12:49 PM »
Your best start is to wire all the positive leads to one power wire and all the negative leads to 1 negative wire.
LTZ Cheyenne C20

Offline SquareBody86

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Re: Cab/Clearance Light wiring help
« Reply #4 on: April 17, 2016, 05:42:21 PM »
Sorry about not replying sooner, just got home from my dads.

Right first off it was a kit I got on ebay, it didn't come with instructions that I'm aware of. Mounting wasn't a problem it's the wiring that's getting me and here are a few pics.

what doesn't help is that I can't really find anything to show how to wire these properly ether.





If it ain't broke don't fix it, upgrade it!

'Rusty' 1986 C10 Chevy Silverado, long box fleetside, LG4 305/TH700R4 with Edelbrock 1406, 2.73 rear ratio

Offline bd

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Re: Cab/Clearance Light wiring help
« Reply #5 on: April 17, 2016, 05:54:29 PM »
You need to run B+ and ground to each lamp rather than chain them together.  By wiring "in series" there is insufficient voltage available to the lamps.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline bd

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Re: Cab/Clearance Light wiring help
« Reply #6 on: April 17, 2016, 05:58:24 PM »
Wire all of the red leads together and connect them to B+ through the switch and fuse.  Wire all of the black leads together and connect them to shiny bare sheetmetal.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline SquareBody86

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Re: Cab/Clearance Light wiring help
« Reply #7 on: April 17, 2016, 06:05:20 PM »
Wire all of the red leads together and connect them to B+ through the switch and fuse.  Wire all of the black leads together and connect them to shiny bare sheetmetal.

So just wire all the positives to one wire then all the negatives to another, then just ground the negative?
« Last Edit: April 17, 2016, 07:18:56 PM by SquareBody86 »
If it ain't broke don't fix it, upgrade it!

'Rusty' 1986 C10 Chevy Silverado, long box fleetside, LG4 305/TH700R4 with Edelbrock 1406, 2.73 rear ratio

Offline bd

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Re: Cab/Clearance Light wiring help
« Reply #8 on: April 17, 2016, 09:02:35 PM »
Yes
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline SquareBody86

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Re: Cab/Clearance Light wiring help
« Reply #9 on: April 18, 2016, 08:41:57 PM »
Thank's a bunch! Just got them wired today and they look awesome! I'll put a pick up when I can.
If it ain't broke don't fix it, upgrade it!

'Rusty' 1986 C10 Chevy Silverado, long box fleetside, LG4 305/TH700R4 with Edelbrock 1406, 2.73 rear ratio