Factory trailer wiring harness
#16
01-21-2014, 08:54 AM
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Sounds good, now to consider my options.
If I go to the salvage yard, what range of years might I find the small relay box in? I assume there's no difference between F-series models.
15 years ago I could go to 3 yards during my lunch hour...today, after government intervention and the skyrocketing price of steel, I'll have to drive 45 minutes just to get to a decent yard.
If I go to the salvage yard, what range of years might I find the small relay box in? I assume there's no difference between F-series models.
15 years ago I could go to 3 yards during my lunch hour...today, after government intervention and the skyrocketing price of steel, I'll have to drive 45 minutes just to get to a decent yard.
#18
01-22-2014, 04:26 PM
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Got lucky! Found a 97 F250 in the only "local" yard, and picked up the small relay box and the rear pigtail that plugs into the unused connector. Once I get them cleaned up, connected and soldered, I should be in business!
As usual, kudos to subford for all his sage advice and input!
Guess I'll need to post up some pictures of the new GN trailer that started this mini-project, and the F350 now that the flatbed is installed.
As usual, kudos to subford for all his sage advice and input!
Guess I'll need to post up some pictures of the new GN trailer that started this mini-project, and the F350 now that the flatbed is installed.
#19
01-22-2014, 10:59 PM
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Everything fit, plugged in, and works like a charm. Got the rear trailer connections all buttoned up, too. Some rewiring to do on the taillights and flatbed, as the installers didn't have much to work with that day. Working for now, though...and there are a couple of trailer jobs to tackle first.
Here's the small relay box installed. Very nice that both relays worked and nothing needed debugging.
Here's the small relay box installed. Very nice that both relays worked and nothing needed debugging.
#20
07-13-2016, 02:38 PM
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Everything fit, plugged in, and works like a charm. Got the rear trailer connections all buttoned up, too. Some rewiring to do on the taillights and flatbed, as the installers didn't have much to work with that day. Working for now, though...and there are a couple of trailer jobs to tackle first.
Here's the small relay box installed. Very nice that both relays worked and nothing needed debugging.
Here's the small relay box installed. Very nice that both relays worked and nothing needed debugging.
Edit I now know what pigtail i need for the rear end. Thanks anyways!
#21
06-17-2018, 01:16 PM
Old thread I know but I have a question.
I had picked up the 2 relay box at some point and am looking to re do the trailer brake controller on my 93 F150 w/ 5.0.
My under hood harness doesn't appear to have the two round connectors needed to plug in the relay box.
My PDB doesn't have the connections in to the empty maxi-fuse slot @ 21 or on relay 4
But I do have the under dash factory connector for trailer brake controller
Am I out of luck for a simple plug and play (without opening the PDB and reconfiguring) or was the wiring different for earlier years?
I had picked up the 2 relay box at some point and am looking to re do the trailer brake controller on my 93 F150 w/ 5.0.
My under hood harness doesn't appear to have the two round connectors needed to plug in the relay box.
My PDB doesn't have the connections in to the empty maxi-fuse slot @ 21 or on relay 4
But I do have the under dash factory connector for trailer brake controller
Am I out of luck for a simple plug and play (without opening the PDB and reconfiguring) or was the wiring different for earlier years?
#22
06-17-2018, 02:21 PM
#25
06-18-2018, 05:30 AM
No, that is stock fuse "E" in the engine fuse relay box.
That jumper and cut wiring was to only give power to the the brake pressure switch with the key on. The old way was to give power with the key off and caused some fires while parked. So it just did this as an extra safety thing I put in. The re-call is not showed but it is in the wire #10 also.
Fuse "E" location.
Attachment 280139
Stock Fuse relay box for a 1993 without factory tow.
/
That jumper and cut wiring was to only give power to the the brake pressure switch with the key on. The old way was to give power with the key off and caused some fires while parked. So it just did this as an extra safety thing I put in. The re-call is not showed but it is in the wire #10 also.
Fuse "E" location.
Attachment 280139
Stock Fuse relay box for a 1993 without factory tow.
/
#26
06-18-2018, 07:59 AM
#28
06-19-2018, 08:51 AM
#29
06-19-2018, 09:06 AM
#30
07-07-2021, 08:27 PM
Wow...35K miles...I have that same truck, but 170K miles...and also rust-free 
.
I have read every thread I can find on factory trailer wiring, but am still troubled by what I'm finding on my truck. One of the PO's had wired in a 6-pin plug, and it had a gooseneck ball and a reported history of pulling horse trailers, so I have to think the aftermarket (Kelsey) brake controller was working at one time. However, the terrible state of some of the wiring work has me wondering if it ever did.
Here's where I'm confused.
1) I do not have the secondary set of boxes next to the main fuse/relay panel under the hood. Here's a picture, showing the two unused connectors on the fenderwell.
2) I have the two connectors near the rear taillight connector. Connector 2 has the trailer lights (left, right, running, ground), and connector 1 has what looks like trailer brake, battery charge, and perhaps back-up? Note the circled area where the 6-pin connector's trailer brake pin was redneck-wired to by scraping insulation, wrapping (no solder) and black tape.
3) Last, I have a 4-pin plug under the dash (shown below) that the Kelsey controller is wire-tapped into. I haven't undone all the black tape to see exactly what other connections exist, but this is as I purchased it.
So based on what I've seen in other threads, I don't have the factory wiring harness, but I need to sort out what I do have and make it work. What I'd really like to know is how to tie in the under-dash connector to the wiring harness feeding that rear connector...if I could find it. Is it one of the plugs I marked above next to the fuse box?
Advice/clarification welcome...
thanks...Paul
.I have read every thread I can find on factory trailer wiring, but am still troubled by what I'm finding on my truck. One of the PO's had wired in a 6-pin plug, and it had a gooseneck ball and a reported history of pulling horse trailers, so I have to think the aftermarket (Kelsey) brake controller was working at one time. However, the terrible state of some of the wiring work has me wondering if it ever did.
Here's where I'm confused.
1) I do not have the secondary set of boxes next to the main fuse/relay panel under the hood. Here's a picture, showing the two unused connectors on the fenderwell.
2) I have the two connectors near the rear taillight connector. Connector 2 has the trailer lights (left, right, running, ground), and connector 1 has what looks like trailer brake, battery charge, and perhaps back-up? Note the circled area where the 6-pin connector's trailer brake pin was redneck-wired to by scraping insulation, wrapping (no solder) and black tape.
3) Last, I have a 4-pin plug under the dash (shown below) that the Kelsey controller is wire-tapped into. I haven't undone all the black tape to see exactly what other connections exist, but this is as I purchased it.
So based on what I've seen in other threads, I don't have the factory wiring harness, but I need to sort out what I do have and make it work. What I'd really like to know is how to tie in the under-dash connector to the wiring harness feeding that rear connector...if I could find it. Is it one of the plugs I marked above next to the fuse box?
Advice/clarification welcome...
thanks...Paul
. also there are connectors that are called T-1 one connectors but they only go to a 4 flat hook up.
Last edited by Paul J Conroy Sr.; 07-07-2021 at 08:30 PM. Reason: adding in additional info
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