Help ! Getting 24 volts in my 12 volt system !

[Starlight]

Hey guys, Any idea why I"m getting 24 volts in my 12 volt system . M1009. Now I know why the headlights were not working. they were blown ! Other lights WAY bright so put a meeter to them and WOW ! Thanks forany advise,T

 

[85-m1028]

you should have a single wire comming from + side of the front batt to the smaller diamond shaped power block on the firewall.

sounds like you got the wiring mixed up? take a volt meter and read + terminal at the front battery it should be 12v and the + terminal at the rear battery should be 24v.

if you could post a few pics of the batteries and wiring it might help.

 

[m4A1]

The junction boxes on the passenger side firewall and next to the rear seat are 24v. There are also a 24v source at the fuse box and for the starter relay. Check and make sure all are isolated from the 12v system.

 

[Starlight]

I have the "single wire" coming off the rear battery to the diamond. Reading 24 v. Are you sure. Looks like original wiring . Thanks

 

[Starlight]

rear battery

Here's a shot of what I have. Was this wired wrong from the git go ? Is that small red cable off of the positive supposed to be off front battery ?

 

[Recovry4x4]

RE: rear battery

Wait for an expert but I think your synopsis is right. If it weren't for having a housefull of kids,I'd bring Devilman96s 1009 over to compare them, it's here at the house.

Edit, here are 2 pics I just took.

 

[Starlight]

RE: rear battery

Holy CRAP ! The small cable is running off the back positiive, delivering 24 v. to truck systems ! No wonder we're blowiong bulbs etc. and no wonder there are shunts at the relays... to protect them ! Wow, learned a lot on this one guys. Someone didn't know the system and I'm affraid it's the guy who redid the battery cable ends for me. Thanks for all the help, we'll see how much damage has been done, T

 

[Crash_AF]

RE: rear battery

Yep, that would be your problem, the small red cable is supposed to run from the back negative or front positive to deliver 12V to the truck.

Later,
Joe

 

[AJMBLAZER]

RE: rear battery

Subscribed...





Just as a bit of advice, I took a black permanent marker, cleaned the boots and ends of the battery cables up nice, and then labelled them "front pos to rear neg", "front neg", etc according to their positions and where the wire came from. That way if I get confused all I have to do is read them and connect them to the battery as such.

 

[Starlight]

RE: rear battery

Darn good idea. I don't know how everything including alternators were not destroyed with 24 v. running through them. Now I "think" I know what those shunts were for befor relays. They're probably to protect the relay from over voltage. Thanks for everyone's help here. Also, finally found the manuals on here. Whatever I printed out led you to "see your supervisor" every time I got near the issue. Well, I've been out of the service for many years so ....I don't have a supervisor...sept the wife of course. Take care, T

 

[Michael]

RE: rear battery

That just means you need to go to the next higher level of manual. You can't just start with the highest level manual because it will usually assume that all of the lower level stuff has already been done.

 

[beetleswamp]

Re: RE: rear battery

Yep, that would be your problem, the small red cable is supposed to run from the back negative or front positive to deliver 12V to the truck.

Later,
Joe

This is getting a little off topic but seems like an appropriate place to pose this question about my vegoil conversion.

I have a goldenrod filter heated with two 60g glow plugs on a 30amp relay and the instructions say to connect the 30/51 load terminal to a direct 12v power source. Just want to make sure it's okay to go right to the back neg or front pos. I'm running activation terminal through the ign plugs in the fuse block.

Diesel is almost $5.40 a gallon here.

 

[devilman96]

RE: Re: RE: rear battery

Hook up to the front battery...

 

[CCATLETT1984]

RE: Re: RE: rear battery

i agree with Dman, hook it directly to the positive terminal on the front battery with its own heavy guage wire