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BriEOD
06-02-2008, 02:22 PM
I performed a query of the site for previous threads and even conducted a hard search through the trailer category re: the infamous 5pin/4 pin issue, without much sucess.

We are going on vacation on Saturday and would like to take my wife's Expedition in lieu of my F-150. My 2000 PS 205 trailer has flat 5 pin wiring harness and my wife's Expedition is equipped with a flat 4 pin OEM wiring harness. Is is possible to by a "converter" from an auto parts store or Wal-Mart?

ski_king
06-02-2008, 02:33 PM
I can be wrong and I often am but..........

I thought you could plug a 4 pin flat into a 5 pin flat. You will just be missing the 5th pin for brake control.

Some connectors may need to be modified slightly to cut away some of the "boot"

BriEOD
06-02-2008, 02:35 PM
What do I do when I back up?

ski_king
06-02-2008, 02:37 PM
What do I do when I back up?

As I said, I am often wrong..........
I did it years ago on a snowmobile trailer. Trailers with brakes are something I am not familuar with.

NU-skier
06-02-2008, 02:38 PM
West Marine

http://www.westmarine.com/webapp/wcs/stores/servlet/producte/10001/-1/10001/233129?srccode=cii_9686437&cpncode=07-57945984-2

DanC
06-02-2008, 02:43 PM
How do you backup with a four pin connector?
flip the connector around and turn on your headlights

mayo93prostar
06-02-2008, 02:46 PM
You really need the fifth pin to release the brakes when backing up, assuming you have hydraulic brakes on the trailer. The fifth pin is from the backup lights so you could rid it up with a new 5 pin vehicle connector and tap into the backup light wire. You should be able to go get a new T-connector and either 7pin round or 5-pin flat cable that comes from the T down to the trailer. you can not just convert from the 4 to 5 pin because the 4 pin does not have the backup light power.

NU-skier
06-02-2008, 03:13 PM
This adapter plugs into the factory harness and converts it to the 5 pin you're looking for. Looks like a nice addition if you use different pin arrangements often.

http://www.partsamerica.com/productdetail.aspx?MfrCode=HOP&MfrPartNumber=40955&PartType=874&PTSet=A

BriEOD
06-02-2008, 03:20 PM
That would be perfect, but wrong format.

The vehicle is a flat 4 pin and the trailer is a flat 5 pin.

NU-skier
06-02-2008, 03:43 PM
That type of adapter plugs into the harness under the bumper. It will replace the 4 wire flat that you have now.
My Tahoe is running a harness adapter that plugs into the factory wire harness just like this one.

BriEOD
06-02-2008, 03:51 PM
Let me go look.

NU-skier
06-02-2008, 03:54 PM
http://www.amazon.com/gp/product/B0002RNS82

This is what should be plugged into your harness now. (4 pin)

CBergerson
06-02-2008, 04:02 PM
http://www.amazon.com/gp/product/B0002RNS82

This is what should be plugged into your harness now. (4 pin)

He needs an extra wire coming from the reverse lights that will lock out the surge brake on the trailer when backing up.

Flipping the 4-way connector over and turning on the headlights will work for the short term, but he needs something more permanent. I would replace the 4-way flat with a 7-round RV connector and just run a wire for the brake lockout from the reverse lights on the vehicle.

NU-skier
06-02-2008, 04:06 PM
That link was to show him what he has on his truck now. (without the 5th wire support). If he replaces it with a 5 pin harness or a 7 pin harness with a 5 pin adapter, the brakes will work as designed.

http://www.acehardwareoutlet.com/(ffuvwuvdfkyl1a55yelb0b55)/ProductDetails.aspx?SKU=8204182
This is the 7 pin to 5 pin adapter required with the 7 pin harness.

bigmac
06-02-2008, 04:07 PM
I don't think there's an adapter from 4 flat to 5 flat...you need an installed 7 pin round to 5 flat to send the backup light signal.

Only solution...run a separate wire from your vehicle's backup lights to the 5th pin on the trailer connector.

CBergerson
06-02-2008, 04:09 PM
That link was to show him what he has on his truck now. (without the 5th wire support). If he replaces it with a 5 pin harness or a 7 pin harness with a 5 pin adapter, the brakes will work as designed.

So, the Ford harness has the reverse light wire in it as long as you have the 5-pin or 7-pin connected to it? I didn't know that.

NU-skier
06-02-2008, 04:15 PM
Mac... I can't find a pure adapter either. Just the replacement harness to replace the 4 pin flat that is on there now.
I would upgrade to the 7 pin round. Then use the coiled adapter to run to the trailer or upgrade the trailer to match the 7 pin round.
I still have the old school 4 wire. Maybe for my b-day someone will get me a new boat with this issue. :)

This link shows the Ford wire colors for 7 pin: http://www.etrailer.com/faq_wiring.aspx

wakeX2wake
06-02-2008, 04:21 PM
I didn't think MC ever put electronic brakes on their trailers... i thought the trailer brakes on MC trailers were hydraulic compression?... meaning that the brakes are activated when the tounge of the trailer slides into itself... i've never had a problem backing up but i've also had a five pin flat on the yukon and now the tundra

92 190 PS
06-02-2008, 04:23 PM
As bigmac mentioned above the only thing I believe can be done is run a seperate wire (jumper) from your back-up light on the truck. I did the same on my Pilot so that I could tow my brothers X-9 from time to time. If you need pictures of the process let me know and I'll get you some tonight when I get home. Very simple....

92 190 PS
06-02-2008, 04:26 PM
OK I stand corrected....Just found this. This might do it. Looks like the jumper I made myself...Good luck.

http://store.drawtite.com/20136.html

bigmac
06-02-2008, 05:25 PM
There are plenty of 7-pin round to 5-pin flat adapters on the market - most MasterCraft dealers carry 'em. I agree that the most logical solution would be to convert the 4 pin flat on the Expedition to a 7-pin round socket, buy the 7-round/5-flat adapter. Alternatively, BriEOD might be able to find a 5-flat female plug as below, wire the 4 wires for it to the same leads as the 4-flat, then tap into the backup light wire for the 5th pin with one of those blue 3M connectors to get it into the backup lights. That would probably be simpler, assuming he doesn't need to ever hook up a trailer with electric brakes.


http://shop.easternmarine.com/index.cfm?fuseaction=catalog.prodInfo&productID=4998&categoryID=209
http://shop.easternmarine.com/images/product/4998.jpg

BriEOD
06-02-2008, 06:22 PM
There are plenty of 7-pin round to 5-pin flat adapters on the market - most MasterCraft dealers carry 'em. I agree that the most logical solution would be to convert the 4 pin flat on the Expedition to a 7-pin round socket, buy the 7-round/5-flat adapter. Alternatively, BriEOD might be able to find a 5-flat female plug as below, wire the 4 wires for it to the same leads as the 4-flat, then tap into the backup light wire for the 5th pin with one of those blue 3M connectors to get it into the backup lights. That would probably be simpler, assuming he doesn't need to ever hook up a trailer with electric brakes.


http://shop.easternmarine.com/index.cfm?fuseaction=catalog.prodInfo&productID=4998&categoryID=209
http://shop.easternmarine.com/images/product/4998.jpg

This looks to be my best and most cost effective course of action. I had to run some errands and went by the auto parts store. They had this adapter for $5. The only labor on my part is identifying and jumping the reverse lights off of the host vehicle.

My F-150 in equipped with a 4 pin flat and 7 pin round. Unfortunately, the Expedition is only equipped with a 4 pin flat. Although the F-150 is a SuperCrew, I don't have a DVD player which the Expedition does have. On a long trip it certainly helps entertain the kids. What did we ever do when we were kids?

Thx guys.

BriEOD
06-02-2008, 09:46 PM
Well, this was easier than I thought. Upon further inspection, the nice folks at Ford has already run the 5th wire to the rear of the vehicle and capped it off. It was taped to the rest of the wiring harness. I used a little blue plastic splicer and some liquid electrical tape and all is good.

bigmac
06-03-2008, 01:02 AM
Well, this was easier than I thought. Upon further inspection, the nice folks at Ford has already run the 5th wire to the rear of the vehicle and capped it off. It was taped to the rest of the wiring harness. I used a little blue plastic splicer and some liquid electrical tape and all is good.

Cool. And for $5 plus the cost of the little blue splicer.

milkmania
06-03-2008, 05:32 AM
Cool. And for $5 plus the cost of the little blue splicer.

but, the big question is......

does the DVD player still work?:uglyhamme

BriEOD
06-03-2008, 09:39 AM
Cool. And for $5 plus the cost of the little blue splicer.

Splicer came in the kit.;)