12 volt CUCV headlights keep blowing

[cheddabob66]

Hello all First post here, I recently purchased my first project and its a 84 m1009 with 60k on it not to bad shape and still running. So far changed all fluids, filters, plugs, tires, and transferred the new red tops to the cab under the passenger seat to make room for the turbo in the engine compartment. Still running 24v system. For some reason ever since I moved the batteries I have been blowing the headlights (2 sets), the parking/signal/brake lights stay on (no blinking), and I am getting 22.9 volts at all my lights. can't seem to figure this out any one have any ideas.

 

[steelandcanvas]

Welcome! Start with the CUCV Sticky:

http://www.steelsoldiers.com/showthread.php?123199-CUCV-Helpful-Threads

 

[gimpyrobb]

Check your grounds.

 

[firefox]

Am I missing something, but shouldn't he have 12 v to the lights. If
he has a bad ground, is it possible to end up with 24 v to the lights?
Just trying to stay on track.

 

[gimpyrobb]

I don't know cucvs that well, but it sounded like he moved the batterys. If he did, he might have missed an isolated ground which is putting 24v into 12v stuff.

I am not sure, just thinking that might be it.

 

[Warthog]

Batteries are wired incorrectly.

 

[cheddabob66]

WOW...you guys are great I didn't expect this may replies so fast - awesome. I am currently reading through the sticky left by steeland - thanks by the way wort hog gave and lengthy but detailed electrical description so it will take me some time to go through all the wires. I did move the batteries to inside the cab but I meticulously moved each piece one by one so as not to wire it incorrectly, however I will disconnect and reconnect everything one more time as per diagrams left by warthog. Again thanks guys you are awesome.

 

[cheddabob66]

oh yeah just to verify brake lights, trailer plug and parking markers are all getting around 22 volts and staying on. not blinking just solid, but not blowing either however whenever I plug a headlight up it immediately lights then blows

 

[frodobaggins]

That's what happens when you put double the voltage in. Stop putting lights in until you diagnose the electrical problem. All your lights should have around 12v.

 

[Recovry4x4]

Some of the connections on a CUCV "can't possibly be right" to folks that don't know them. You may have corrected an obvious error that really wasn't.

 

[MarcusOReallyus]

Batteries are wired incorrectly.

Some of the connections on a CUCV "can't possibly be right" to folks that don't know them. You may have corrected an obvious error that really wasn't.

That's what happens when you put double the voltage in. Stop putting lights in until you diagnose the electrical problem. All your lights should have around 12v.

Er, I guess that should be, what they said.

 

[cpf240]

My guess is that the 12v feed that goes between bat 1 and bat 2 is connected to the wrong place.

 

[MarcusOReallyus]

My guess is that the 12v feed that goes between bat 1 and bat 2 is connected to the wrong place.

No, I don't think that would do it. I think it's more likely that he's got a 24v feed going to the 12v buss.

 

[cpf240]

No, I don't think that would do it. I think it's more likely that he's got a 24v feed going to the 12v buss.

That is exactly what I meant... that the feedline to the 12v buss is *not* connected between the two batteries, but at the end of the chain, thus getting 24v...

 

[TechnoWeenie]

Does OP realize that the ONLY thing that gets 24V is the starter and glow plugs, and everything else gets 12v?

I'm thinking he put the 12V feed on the + of the second battery and is now pushing 24V through his 12V system.

 

[cheddabob66]

Ok guys I think I got it, just checked back in and I figured out I probably crossed my 12v and 24v lines. Now my voltage b us around 11v at all lights and 22v to the gp relay, thing is my lights still stay solid no blinkers and no brakes just lights

 

[MarcusOReallyus]

If you have the correct voltages where they should be, now you can start troubleshooting the other problems. You pushed 24v through a 12v system, so it's likely you blew a fuse or two, or fried a blinker module.

 

[Barrman]

Each battery should be fully charged and load tested. That means 12.6 volts per battery with the engine off. Each alternator should put out 14.4 volts when running.

That means your 11 and 22 volts is way off. I know you are tracking down issues, but starting with fully charged batteries really is a good idea. Not just because it is the very first thing listed in the electrical troubleshooting section of the manual.

The brake light signal goes through the blinker system. So I would suggest checking the blinker fuses, blinker wiring plug on the bottom of the steering column and following the wires to the rear of the truck from the firewall.

 

[cheddabob66]

hay guys finally got the voltage right in al the right places, brake lights work, hazards work and headlights work - but blinkers still stay solid when lever is switched. Voltage at lights are 10.58 but at the relay/fuse I am only 2.88 volts when the switch is on. could there be resistance at the switch if something was blown during my 24v debacle??already ordered all the replacements so getting new parts anyways just wondering if anyone has had this issue before. thanks for the help.

 

[TechnoWeenie]

hay guys finally got the voltage right in al the right places, brake lights work, hazards work and headlights work - but blinkers still stay solid when lever is switched. Voltage at lights are 10.58 but at the relay/fuse I am only 2.88 volts when the switch is on. could there be resistance at the switch if something was blown during my 24v debacle??already ordered all the replacements so getting new parts anyways just wondering if anyone has had this issue before. thanks for the help.

You probably toasted the THERMAL flasher.. It heats up, bends a contact, which breaks the connection, cools down, touches, bends back, etc... running 24V through it probably toasted it.

The newer electronic versions are like 5$...