CUCV no lights

[WeldSpatter]

Hey y’all, I need me some help. Been lookin on this site for couple months now. I’m 17 and bought an m1008 a couple months back, and have been wrenching on it. Bout 2 months ago I went to take it for a test drive after installing a OEM style steering column , and went to turn the lights on and nothing. I had no headlights, no tail lights, brake turns etc. went to my buddy and he said that half the fuse panel wasn’t gettin no power. Truck runs, drives, charges, accessories work( for the most part, bad sending unit ) but I have no lights at all. Can any of y’all point me in the right direction. Wiring diagrams, or possible culprits, etc. I’ve heard that fuseable links could be it, but my reasoning is telling me either the resistors or the junction box is the 2 things between the battery and the panel.

Any help is appreciated, I’m a broke kid tryin to make things work. Have a blessed day.

 

[diesel583]

Hey y’all, I need me some help. Been lookin on this site for couple months now. I’m 17 and bought an m1008 a couple months back, and have been wrenching on it. Bout 2 months ago I went to take it for a test drive after installing a OEM style steering column , and went to turn the lights on and nothing. I had no headlights, no tail lights, brake turns etc. went to my buddy and he said that half the fuse panel wasn’t gettin no power. Truck runs, drives, charges, accessories work( for the most part, bad sending unit ) but I have no lights at all. Can any of y’all point me in the right direction. Wiring diagrams, or possible culprits, etc. I’ve heard that fuseable links could be it, but my reasoning is telling me either the resistors or the junction box is the 2 things between the battery and the panel.

Any help is appreciated, I’m a broke kid tryin to make things work. Have a blessed day.

 

[diesel583]

Ok I pushed wrong button so , I'll try again, Be sure and read the manuals they are available hear free, I've been a Mechanic for 60 years and still go to the books. Don't guess you will work for a week on a easy job. Just a hint is the service light switch on?

 

[Keith_J]

Blackout switch? Left side toggle switches. Needs to be on SERVICE DRIVE. These control relays, check those. Download the -20 TM, it has wiring diagrams and troubleshooting.
If it starts, runs and drives, your issue is most likely with the blackout system. There are LED lights on all 4 corners, markers up front and markers+brake on rear. Has to be dark to notice, do these illuminate?

 

[WeldSpatter]

Ok I pushed wrong button so , I'll try again, Be sure and read the manuals they are available hear free, I've been a Mechanic for 60 years and still go to the books. Don't guess you will work for a week on a easy job. Just a hint is the service light switch on?

On an in the up position, I never expected none of this to be easy, an I’m ready for the challenge.

 

[cucvrus]

Check the 30 amp fuse about 1/2 way up on the right side of the fuse box. Is it semi melted and loose? That can be the issue. I split the contention at the bulkhead and add 2 inline sealed fuse holders. One will serve the lighting system and the other is the brake lights. Put a circuit breaker in place for the 30 AMP fuse and all will be well. I hope that helps. Check it out and report back. These trucks are basically the same as every civilian Chevrolet truck ever built back in that era. A few extra things that are still very crude in fit finish and design by todays standards. Good Luck. Report Back if you have any other issues.

 

[WeldSpatter]

Check the 30 amp fuse about 1/2 way up on the right side of the fuse box. Is it semi melted and loose? That can be the issue. I split the contention at the bulkhead and add 2 inline sealed fuse holders. One will serve the lighting system and the other is the brake lights. Put a circuit breaker in place for the 30 AMP fuse and all will be well. I hope that helps. Check it out and report back. These trucks are basically the same as every civilian Chevrolet truck ever built back in that era. A few extra things that are still very crude in fit finish and design by todays standards. Good Luck. Report Back if you have any other issues.

When I first found the problem it was a blown fuse. I replaced the fuse, but it just blew the fuse and all lights went out, this happened multiple times. I’ll be sure to report back when I try out the fix. I really appreciate the help.

 

[cucvrus]

Check that 30 AMP fuse is it blowing or melting from a loose resistance connection? I have seen that same 30 AMP near melted in half and still holding current. If you are blowing the fuse and it is seated tightly in the fuse box you have other issues that need corrected. I am here to help anytime. Good Luck.

 

[Ferroequinologist]

That section of the fuse box is almost always damaged from overheating, and making bad connections. Best thing to do is switch to LED lights, or put a relay in-between like I did. Lets a separately fused circuit straight from the batteries to feed the headlights, and the switch and 30amp on the fuse box just sends the signal.