Bri-Mar Dump Trailer Battery Charging automatically ?

[FritzII]

Diamondpilot, Chevy ( in 08 ) leaves the fuse out and does not connect two wires under the hood. ( In my 04 I just had to put the fuse in. ) There is one hidden behind and to the right of the fuse box and the other is down by the steering column where it comes through the firewall. You must connect these to metric studs in front of the fuse box. There is a 40 amp stud and a 30 amp stud. I installed the brake controller and added the fuse and connected the 2 wires in front of the fuse box under the hood. The receptacle pin gets 12v off & 14v while the truck is running. The receptacle is wired properly and all the pins do what they are supposed to.

I did not buy this trailer new & it turns out that the pigtail is bad. I can not get continuity on the 12 volt charge circuit. I suspect that the problem is in the 7 pin plug connections. I have checked all 6 wires in the pigtail and 5 of them read good. The 12 volt charging ckt is bad. It's good from the battery to the harness. It's bad from this point to the truck. I am going to cut the plug off to see if that's the problem. The wire is either melted or not connected inside the plug.

Thanx for all the help and thoughts guys!!!!!

[Diamondpilot]

Fritz

Glad you got it figured out. Sounds like GM changed things once again, installing wires to studs is a new thing and the ones I have worked with use only one fuse. Like I said I have installed controllers in GM trucks up to 07 but not 08 so sorry if I gave you wrong advise. I have never seen a truck give voltage on the charge circuit with the truck off but that seems to be another change. Usually with the key off there is no voltage at the trucks plug. Seems like if you hooked up a trailer with a dead battery and say left it over night you could come back to a truck that may not start due to the draw on the trucks battery. I can not wait to have to wire up one of these new trucks and will probably be getting in touch with you since you are now the 08 GM guru.

Chris

[FritzII]

I wondered about discharging the battery also, but the truck has some kind of disconnect so the battery won't drain below a certain voltage.

Don't ask me what the stud sizes are !!! I dug around in my metric motorcycle parts to find nuts to fit the studs.

Hacker may be a better term than Guru !!!

[wkpoor]

My charge wire is hot to the back. Here again its never been an issue. The way I look at it the trailer battery is on the bus the same as the truck battery just a little further away. Since I've never had a problem with it I never knew if something was done wrong there.

[FritzII]

There was something wrong in the molded plug. It now charges with a new plug installed. I also took out the 20 amp fuse on the dump battery and installed an automotive 20 amp circuit breaker.

[wkpoor]

There was something wrong in the molded plug. It now charges with a new plug installed.

I had the exact same problem last year. I lost the charge circuit and it ended up being in the molded section right behind the plug. It was a Hoppy surface mount with the 4 flat next to the 7pin round.