No constant 12V at the 7 Pin trailer plug???

[f-two-fiddy]

I was under the assumption that the OEM 7 pin had a KO 12v pin?

My truck has the original Ford branded 7 pin installed, all OEM wiring, yet I do not get 12v constant (trailer battery charge) at any pin.

Am I missing a fuse? Under hood fuse panel? In cab?

 

[Clb]

Under hood I think?
What year?
I can check an 88' 93 fsm

 

[jwalterus]

check behind it, if there's no wire hooked up to #4, put one in

a lot of them are just wired as a 4-way so people only have to have one type of plug on all their trailers instead of having adapters

 

[OLDBULL8]

If the truck came with the tow package, there will be a relay under the hood on drivers side next to the firewall, when you turn the key ON, it energizes that relay for the 12 VDC for the battery charge circuit to the trailer. You have to have the key ON to check it at the 7 pin.

It may be a fusible link or a fuse for the trailer battery charge circuit.

 

[riotwarrior]

It shouldnt be constant 12 v KO yes...for safety and so u dont drain bat parked over night.

 

[f-two-fiddy]

This is on my '93

I've done a little research and found what appears to be the '93 diesel under hood fuse panel. I do have the relay listed as "trailer battery charge" I did have the engine running when I probed for KO 12V.

Maybe I'll have to disassemble the male plug end and see if the wire is disconnected? Is there a fuse somewhere for trailer batter charge? I don't see it listed on the under hood fuse panel.


http://www.ford-trucks.com/forums/attachment.php?attachmentid=20104&d=1263012198

 

[pastorjeep]

On my 89 with what looks to be factory tow package (the seven way has ford stamped in the aluminum housing) the wires are all chewed up. Can you show me a picture of your factory plug?