12 Volt to a trailer

[ISurvivedNMU]

I have a 2003 chevy 2500HD and I have no power to the rear trailer Hookup... I think I read somewhere that I need to buy a fuse... Can I get this at auto zone and what is it... Help!

Brian

 

[ISurvivedNMU]

FYI, its a 40 amp fuse that goes in the fuse box under the hood... There is a red fake fuse in there from the fatory... Replace it with the 40... and the brake controller will be powered up and your trailer also... I guess the 2004's come with the fuse and brake controller wiring...

 

[Big K]

That seems like a LOT of fuse.

 

[ISurvivedNMU]

LMAO.... I am in the 120/240 world.... is amp the wrong word......lol

Its a 40 ________?

 

[Max Power]

amp

 

[Max Power]

you should be able to buy it anywhere that sells fuses. Steal one of the other ones to make sure you get the right style. Fuses change daily, everyone uses different style fuses now. It is a pain in the ass! You could also go to your GM dealer and get one but you will pay more.

 

[ISurvivedNMU]

Most likely your trailer store will give you one!!!

 

[Big K]

Guess that's not out of the ordinary. Mine's 40A also.

Something to consider, however, is that if you intend to draw a lot of juice to power 12v lighting/accessories inside your enclosed trailer, you might want to check the capacity/size of the wire that supplies your 12v Batt+ post @ the plug. They are usually not larger than 14ga, and won't live with lots of juice.

It's pretty simple to pull a new, heavier gauge, fused supply.

 

[ISurvivedNMU]

I dont pull a lot of power.. I only use my portable welder... .... Just kidding.... Only a few lights...

Check this, there is a battery in the trailer... Used only for the electric brakes.... if it were to become disconnected from the truck... This battery is not charged when plugged into the truck... it makes no sense.... Also, why not replace that with a larger battery that would support the lights and the brakes while unplugged.... I think it would be smarter.... And have it charge when plugged in.... To me thats a no brainer.. But there must be a reason not to do it..... Anyone.....

 

[Max Power]

no reason, campers opperate the way you think it should be done. Unless there are state laws that require a dedicated brake away battery. I doubt it though.

 

[ISurvivedNMU]

I got it done... Kinda was a pain in the ass, But I learned a lot about my trailer wires.... Like dont touch the large white one..... ... It the power for the trailer brakes... LMAO... It was fun... Took up a lot of play time... But done the road it will bne worth it..... Thanks for the help guys!

B

 

[Big K]

Originally posted by ISurvivedNMU
I dont pull a lot of power.. I only use my portable welder... .... Just kidding.... Only a few lights...

Check this, there is a battery in the trailer... Used only for the electric brakes.... if it were to become disconnected from the truck... This battery is not charged when plugged into the truck... it makes no sense.... Also, why not replace that with a larger battery that would support the lights and the brakes while unplugged.... I think it would be smarter.... And have it charge when plugged in.... To me thats a no brainer.. But there must be a reason not to do it..... Anyone.....

My Haulmark came equipped with a trickle charger for the breakaway battery. Someday I'll get around to upgrading to a full sized one. It would be nice to be able to use the lighting when unplugged from the tow rig. You'd just need a diode for the 12v feed to the lights/accessories.

We equipped the new open car hauler with a full sized battery, and I'm picking up the trickle charger for that today, along with a few other things. Just got the winch wired up and the mount completed.

 

[ISurvivedNMU]

I guess I did mine a little less complicated... My breakaway battery, is now a full size battery that doubles as the trailer light battery....... I also wired it up so you can plug in 12v accessories to it through cig plugs in the front and back.... Handy for radios... spot lights and such.... Then I just hooked the battery up to the truck... So its like a third battery... when the truck is running, it gets charged..... The downside is, if the battery is weaker than the truck batterys, it will suck them down.... So, to coulter act that... I put a switch on the inside to allow it to pull power from the truck... So as long as it is not on overnight while not ruinning... I should be OK.....

My brakes still get all thier power from the truck... and only use the battery on breakaway, which i hope never happens.....

 

[Geno]

Dual alternators and 2 batterys in your camper will let you run the fridge on dc going down the hiway, if batterys big enough the fridge will run close to 24 hrs.
Geno