Headlight and turn signal on one side inop

[hooyahdiver]

This is my first post. I have an 86 M1028A2/3 that is in goodshape but the front right headlight and turn signal are inop. From prior experience with an all 24V diesel BJ40 Toyota Landcruiser I had, I know that the headlights are on separate circuits. My question is, what relay or fuse is bad and where is it? If I'm wrong and it's not a fuse etc... what is the problem and how can I fix it?

Question 2: Where are you guys getting non-engine/drivetrain parts for your trucks? Is there something like Year One for the 74-89 Chevy truck? Specifically I want a dashpad and new seat belt assemblies. Parts don't have to be milspec. Thanks ahead.

 

[Cucvnut]

LMC truck has a ton of stuff for chevy trucks. as for the blinkers you have a fuse under the dast in the fuse block and the flasher also is in the fuse block. it could be the actuator arm it self not hitting the detent all the way or you might just need a new blinker switch arm lmc has them so.

 

[Crash_AF]

Welcome to the site...

First off, the headlights are on the same circuit, not separate. You can download the tech manuals from the 'Resources' tab at the top of the page. You are looking for 9-2320-289-##. The wiring diagrams are in the -20 and -34 manuals.

The first thing I would check is the ground on the right side of the truck near the front battery, the ground system in these trucks are VERY important and one broken wire will cause all kinds of problems.

Second, LMC truck is probably the best source for the common parts for these trucks.

So is your 1028 an A2 or A3? If it has a 205 transfer case it is an A2 if it's a 208 it's an A3.

Oh yea,

Later,
Joe

 

[4bogginchevys]

you might have a look at the wire loom that runs across the core support, it may be pinched or have a wire in it that has been spliced from a previous owner, I believe that all light wires are in 1 loom as they go across. good luck

 

[hooyahdiver]

Thanks for all the input. As far as if it's an A2 or A3, I don't know yet. I just bought it yesterday. It's got 35,000miles and has a long bed with dual rear wheels which is the only indicator I have that it a M1028 anything. It came from a guy who bought it last month at a GSA auction so it's fresh out of government stables. It's in good shape for it's age and it runs great so I couldn't pass it up. I've wanted one of these vehicles for years. A plus is that I'm still active duty in a unit with a full motor pool filled with knowledgeable folks eager to help. I'll post photos as soon as I have a chance.

 

[Crash_AF]

you might have a look at the wire loom that runs across the core support, it may be pinched or have a wire in it that has been spliced from a previous owner, I believe that all light wires are in 1 loom as they go across. good luck

That is correct, they are all in one loom that comes from the firewall main plug along the inner fender, goes through the support behind the overflow bottle, runs outside just under the bottom of the grille, and back in where the NATO slave cables go through. There is a ground on the left side under one of the radiator overflow bottle mount and there is one on the right side near the front battery.

If it is a true A2/A3 and not a FD modification then there will be a MWO placard under the serial number plate in the driver's door jamb. Either way, nice find and good luck with it.

Later,
Joe

 

[319]

Try your local salvage yard(s) for parts. Lots of similar civilian trucks out there.

 

[Screamin' Metal]

Both the Generals....do EXACTLY as they told you....or your gonna have to drop and give them a bunch o pushups.......

The CUCV's aren't friendly to the novice, unless you got a wrench of many years experience....(me)....alot of parts you can use civi-parts....though you gotta know whats been changed by the DoD....

 

[southdave]

I bought a new headlight harness from a guy(walkers) in cali, for 60 bucks FYI

 

[hooyahdiver]

That is correct, they are all in one loom that comes from the firewall main plug along the inner fender, goes through the support behind the overflow bottle, runs outside just under the bottom of the grille, and back in where the NATO slave cables go through. There is a ground on the left side under one of the radiator overflow bottle mount and there is one on the right side near the front battery.

If it is a true A2/A3 and not a FD modification then there will be a MWO placard under the serial number plate in the driver's door jamb. Either way, nice find and good luck with it.

Later,
Joe

Thanks. I'll get out there and check that wire harness tomorrow. Sounds like it could be the culprit since the only things effected are the headlight and the turn signal on that one side.

There is no placard under the identaplate. I don't know what an "FD" modification is but that may be the case. I literally just got it home and in my yard. I haven't had a chance to tinker with it yet. The rear springs are beefier than on a single axle CUCV. Thanks again for the advice.

 

[Crash_AF]

FD is Fire Department modification. If it came from GSA and not GL, it could have been used by a forest service as a fire vehicle and they can make a bunch of modifications.

BTW, a civvie headlight harness may not work because of the blackout lights. They are in the same harness as the headlights so there's a chance that the civvie harness won't be wired the same at the bulkhead. I purchased a replacement harness for my 1009 because of all of the problems I had with it.

Later,
Joe

 

[SPECIALTYLC]

Lets be sure you checked the obvious first. Did you check to make sure the bulbs were good. Maybe just a coincidenece that both are not working.

 

[Screamin' Metal]

Thanks. I'll get out there and check that wire harness tomorrow. Sounds like it could be the culprit since the only things effected are the headlight and the turn signal on that one side.

There is no placard under the identaplate. I don't know what an "FD" modification is but that may be the case. I literally just got it home and in my yard. I haven't had a chance to tinker with it yet. The rear springs are beefier than on a single axle CUCV. Thanks again for the advice.

Let me also add, sometimes the motorpool folks repair the crossover wires that come out of the main light harness, almost directly below the puck bottle on the drivers side of radiator.
When these trucks are run....they'll 'puck' coolant onto those wires.....and it'll insulate them. Also....it'll mess with the ground...just as our General said.......

Happy Hunting!......be sure to climb under there with a needle pointed test light so youc can probe your wires thru the insulation while leaving your lights on....

 

[hooyahdiver]

I bought a new headlight harness from a guy(walkers) in cali, for 60 bucks FYI

There's a harness strictly for the headlights? Can it be easily detached from the main harness coming out of the firewall? Thanks ahead.

 

[hooyahdiver]

Lets be sure you checked the obvious first. Did you check to make sure the bulbs were good. Maybe just a coincidenece that both are not working.

Good call. Not yet. I assumed that since both the headlight and the turn signal are inop on that side that it was a wiring/fuse problem. I still haven't had time to fool around with it.

 

[hooyahdiver]

It belonged the the Tennessee National Guard.

 

[4bogginchevys]

when I got my 1008 the ground wire for the headlights on the drivers side was not hooked up, I discovered it when adding a battery tray there. The headlights/ blinkers were unaffected before/after wire was hooked up...i'm led to believe that the headlights need a good ground, not multiple grounds. good luck

 

[hooyahdiver]

Problem solved. Solution: One headlight DOA and one turn-signal wire FCKD. The halogen bulb inside the glass case was shattered. Also, the ground on the turn signal signal light inside of the socket was broken off. I had to solder what was left of the broken piece of ground to the bulb base. Both work fine now.

 

[southdave]

There's a harness strictly for the headlights? Can it be easily detached from the main harness coming out of the firewall? Thanks ahead.

Yes I installed that one, right above the steering column or there abouts, it is the outside part of the harness guy name in cali walker had them for about 60 bucks, I think he around here or someone knows of him ect.. maybe they pipe in. If you need mine was super crappy cut up and such just easier to swap out took a hour to do it had the motor out

 

[SPECIALTYLC]

See 90% of the time its a simple ordinary problem thats easy to fix. Everyone always assumes it some kind of major electrical problem that CUCVs are suposedly prone to have.