Ford wiring

[AZsix]

I have an  05 Ford Expedition with the tow package. Sunday when I was tracing a light problem I looked at the wiring to the female end on the truck. There is no wire going into the middle hole. This is supposed to be the one that charges the battery and works the back up lights on the trailer. It's not a huge deal to me if I don't have it but if I can have it I would want to have it connected. There is no wire leading back from the front of the truck that would go there. Can I run a wire myself and if so where would I run it from?

Thanks in advance.

[wavery]

I have an  05 Ford Expedition with the tow package. Sunday when I was tracing a light problem I looked at the wiring to the female end on the truck. There is no wire going into the middle hole. This is supposed to be the one that charges the battery and works the back up lights on the trailer. It's not a huge deal to me if I don't have it but if I can have it I would want to have it connected. There is no wire leading back from the front of the truck that would go there. Can I run a wire myself and if so where would I run it from?

Thanks in advance.

If it were me, I'd run it from a spare lug on the fuse panel with a 30amp fuse. On some vehicles, there is an extra fuse lug that works only when the ignition is on. You should be able to find it with a test-light. I would use 12g wire at minimum and 10g would be better. If you go to a marine hardware store, you can get "Tinned" wire. You will never have to be concerned about corrosion.

When I do jobs like that, I like to know that I can do it once and not have to mess with it again.

Some people run the wire right off of the positive side of the battery and put a 30A in-line fuse right at the battery. The problem with that is that it will always be hot, even with the key off. That could be a recipe for a dead battery.

[mach8274]

I have an  05 Ford Expedition with the tow package. Sunday when I was tracing a light problem I looked at the wiring to the female end on the truck. There is no wire going into the middle hole. This is supposed to be the one that charges the battery and works the back up lights on the trailer. It's not a huge deal to me if I don't have it but if I can have it I would want to have it connected. There is no wire leading back from the front of the truck that would go there. Can I run a wire myself and if so where would I run it from?

Thanks in advance.

Is it a 7-pin plug?? If so the middle terminal is for backup lights or auxillary only. The battery charge terminal is the top-right terminal inside the connector.
Your wire colors may differ from this diagram.

Good luck.

Dave

[wavery]

Is it a 7-pin plug?? If so the middle terminal is for backup lights or auxillary only. The battery charge terminal is the top-right terminal inside the connector.
Your wire colors may differ from this diagram.

Good luck.

Dave

Good catch.....I read right over that...

Come to think of it, if you've got an '05 Expedition (I missed that too :p ), the wire is already in the harness.

[austinado16]

I found my auxilary position (center lug) wasn't powered either, but the wire was there, tucked into the harness.  I hooked it up and now have back up lights working on the camper.  It's a nice little mod.

[AZsix]

Is it a 7-pin plug?? If so the middle terminal is for backup lights or auxillary only. The battery charge terminal is the top-right terminal inside the connector.
Your wire colors may differ from this diagram.

Good luck.

Dave

I was under the impression that the center terminal also charged the battery. If all it does is run the back up lights I'm not too worried about it. As long as the battery is charging going down the road I'm good.

Thanks for the help everyone.

[austinado16]

I was under the impression that the center terminal also charged the battery. If all it does is run the back up lights I'm not too worried about it. As long as the battery is charging going down the road I'm good.

Thanks for the help everyone.

It depends on how it's wired.  I tested mine, and sure enough, the tucked away wire was "hot" when the reverse lights came on in the truck.  I already had the charging wire hooked up as in the diagram above, and my battery was getting charged when the engine in the truck was running.

[flyfisherman]

That center "auxillary" post is where I run a seperate hot line (w/fuse) to and that gives me lights and 12V power for the interior of the Starcraft.

[wavery]

I was under the impression that the center terminal also charged the battery. If all it does is run the back up lights I'm not too worried about it. As long as the battery is charging going down the road I'm good.

Thanks for the help everyone.

You still don't know that for sure. You might want to hook up the trailer then take the hot wire off of the camper battery and use a test light to see if it is getting power from the TV. Just ground one side of the test light and put the other side on the disconnected pos battery wire.

Just because the TV has a hot lead doesn't mean that the trailer is wired for battery charging.

[mike4947]

Industry standard uses pin 4 for battery charging and intransit 12 volt power. Pin 7 or the center pin is commonly used only for backup lights.
Six pin connectors delete the 7th/back light pin.
 
http://www.marksrv.com/wiring.htm