Headlight wiring confusing me

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Camar068

Supporting Member
Supporting Member
Joined
Feb 5, 2014
Posts
4,169
Reaction score
3,033
Location
Kentucky
First Name
David
Truck Year
1986
Truck Model
K10/LM7 5.3/4L60e/np208/3.73/32"
Engine Size
10 yrs Air Force
After reading a recent post about HL's not working, I'm confused. I checked the schematics and now it's worse. I'm about to wire up the relays and build my own harness and don't want to make matters worse down the road. I think I could roll with it because it's working now but want to be sure.

Looking at the back of the bulb with center on top I have:

Left Brown =12V Low Beam (measured from chassis)
Center Green = 12V High Beam (measured from chassis)
Right Black = 0v High or Low Beam (measured from chassis)

I've got H4656 bulbs in it. Is this wiring correct? It's not what I'm seeing on the web or around here. Kinda throws a flag up for me, the passenger side won't work unless that side of the harness is grounded to chassis.
 

gmachinz

Harnessworx Inc
Joined
Nov 10, 2012
Posts
762
Reaction score
287
Location
Iowa
First Name
Jabin
Truck Year
1986
Truck Model
K10
Engine Size
350
Both ends of the front lighting harness is supposed to be grounded to core support. The drivers side headlight ground goes to core support along with battery ground and then there is a longer lead that grounds to the top of the framerail above the fuel pump area.
 

Camar068

Supporting Member
Supporting Member
Joined
Feb 5, 2014
Posts
4,169
Reaction score
3,033
Location
Kentucky
First Name
David
Truck Year
1986
Truck Model
K10/LM7 5.3/4L60e/np208/3.73/32"
Engine Size
10 yrs Air Force
so the wire positions I listed above are correct? Sorry I didn't make it clear I was questioning which wire goes where in the plug itself.
 

gmachinz

Harnessworx Inc
Joined
Nov 10, 2012
Posts
762
Reaction score
287
Location
Iowa
First Name
Jabin
Truck Year
1986
Truck Model
K10
Engine Size
350
Yes appears correct to me.
 

Camar068

Supporting Member
Supporting Member
Joined
Feb 5, 2014
Posts
4,169
Reaction score
3,033
Location
Kentucky
First Name
David
Truck Year
1986
Truck Model
K10/LM7 5.3/4L60e/np208/3.73/32"
Engine Size
10 yrs Air Force
Thanks dude
 

Qwk

Full Access Member
Joined
May 22, 2014
Posts
468
Reaction score
55
Location
Cincy
First Name
Craig
Truck Year
87
Truck Model
C10
Engine Size
5.7/T56
After reading a recent post about HL's not working, I'm confused. I checked the schematics and now it's worse. I'm about to wire up the relays and build my own harness and don't want to make matters worse down the road. I think I could roll with it because it's working now but want to be sure.

Looking at the back of the bulb with center on top I have:

Left Brown =12V Low Beam (measured from chassis)
Center Green = 12V High Beam (measured from chassis)
Right Black = 0v High or Low Beam (measured from chassis)

I've got H4656 bulbs in it. Is this wiring correct? It's not what I'm seeing on the web or around here. Kinda throws a flag up for me, the passenger side won't work unless that side of the harness is grounded to chassis.

Can you post up the Headlight schematic? Im chasing down a headlights not working issue as well.:cheers:

EDIT! Never mind. I found them in the STICKY in here. :)
 
Last edited:

Forum statistics

Threads
42,191
Posts
911,021
Members
33,686
Latest member
mmeade
Top