12Volt line on 7 way plug from tow vehicle

[Popga]

Greetings!

Can anyone tell me where the 12V from the tow vehicle goes in the trailer? Just to the battery? I'm starting the trailer half of my DC-DC charger project and will be disconnecting the 12V when I install the Mictuning 7-way box tomorrow and want to make sure disconnecting it will not affect anything other than the battery charging.

Thanks,
Erik

[Jlawles2]

You will have to verify but the incoming 12V + could be tied to the break away switch in the box. Typically from the box it does only go to the battery after that.

[Cate&Rob]

Hi Erik,

The +12V from the tow vehicle connects to a wire going to the RV battery B+. This same wire within the RV is used to supply RV battery B+ to the break-away switch at the pinbox. The other side of the break-away switch is wired to the brake circuit (typically a blue wire). These break-away switch connections are within the connection box that you are replacing. When wiring your DC-DC system you should make sure that you maintain a trailer battery B+ connection to the break-away switch with the tow vehicle disconnected.

Rob

[Scott'n'Wendy]

I just looked at that wire on our 303. It appears to go straight to the +ve bus bar. I didn't unwrap the wiring bundle so I can't be 100% sure there isn't a splice in between.
Country Campers has a post on here somewhere and it explains how disconnecting that wire from the bus bar MAY disable the breakaway switch. You will need to ensure the breakaway sw gets trailer battery power when the truck is disconnected. Which will require a wire or a relay.

[Popga]

Jlawles2
Cate&Rob
Scott'n'Wendy

Thank you for the information. Goes to show that before you start mindlessly disconnecting wires you better be aware of the consequences. Supposed to be in the 50's today in the PNW (Pacific NW) so a good day to climb under and get my back dirty.

Erik

[Popga]

Scott'n'Wendy

Scott, I located the Country Campers thread, https://gdrvowners.com/forum/operati...ay?view=thread
and needed a second cup of coffee to get through it. What a great source of information.

I don't think I correctly linked it here. I read and re-read all the new guy information posts about how to copy and paste a link to a thread, but still can't figure it out.
Any help appreciated.

Hey! I think it worked! please let me know. And thanks to TucsonJim for the lesson form one of his other posts.

Erik

[Scott'n'Wendy]

Popga
Yup, that's the thread and your link posting works fine.