2008 Mountaineer premier 4.0L 2WD trailer brake connections.

[Ed Mountaineer]

Hello I need help with the trailer hook up for a brake controller. I have located the wiring plug under my dash for connecting the brake controller. But cannot find the blue wire near the hitch. I have the flat 4 wire connector for trailer lights, turn lights and brake lights. I would like to know if there is a plug with the blue brake wire and black 12 volt wire near the hitch?

Thanks

Edgar
2008 Mercury Mountaineer
Premier 4.0L 2WD
Sport Utility 4DR

 

[michael loibl]

Mine took a few minutes to find, but it was there on my 2006. I believe it was about 1 foot back it the plastic wire loom with a shrink wrap end on it. Only thing I had to do was run a charge line

 

[michael loibl]

When I get home, I'll peek underneath the truck and try to give u more detail.

 

[96firephoenix]

Edit with other considerations: If you only have the 4-pin connector, you probably also only have the 1.25" receiver. Any trailer that is heavy enough to need brakes is too heavy for the 1.25" receiver or hitch. Also, if you only have the 4-pin connector, you probably don't have the full tow package, which for 2008 included a trans cooler, I think. Lastly, I thought the Premier only got the 4.6 v8...?


On my 02 (admittedly not the same gen as your 08), there was a connector under the RH taillight. I got the 7-pin RV connector and 2" receiver from the junkyard and ran the wiring harness to the factory connector.

I think I remember that the 4th gen factory receiver is welded on instead of bolted, so you may not be able to just grab a junkyard receiver, but you might be able to get the 7-pin harness from a JY and then wire-tie it in place.

 

[Ed Mountaineer]

Edit with other considerations: If you only have the 4-pin connector, you probably also only have the 1.25" receiver. Any trailer that is heavy enough to need brakes is too heavy for the 1.25" receiver or hitch. Also, if you only have the 4-pin connector, you probably don't have the full tow package, which for 2008 included a trans cooler, I think. Lastly, I thought the Premier only got the 4.6 v8...?


On my 02 (admittedly not the same gen as your 08), there was a connector under the RH taillight. I got the 7-pin RV connector and 2" receiver from the junkyard and ran the wiring harness to the factory connector.

I think I remember that the 4th gen factory receiver is welded on instead of bolted, so you may not be able to just grab a junkyard receiver, but you might be able to get the 7-pin harness from a JY and then wire-tie it in place.

Mine took a few minutes to find, but it was there on my 2006. I believe it was about 1 foot back it the plastic wire loom with a shrink wrap end on it. Only thing I had to do was run a charge line

Thanks to both of you for your help.
Michael I checked the harness more than a foot and found no blue wire. I did check for voltage in the plug under the dash on the factory plug and have voltage present. So will continue checking for a connector.

96firephoenix You are right on the 1.25" receiver And I am limited to 3500 lbs pull weight. My RV is 3200 lbs only 14 ft long. Though I appreciate your concern. The RV does have electric brakes though and I would like to use them when we travel in the mountains. I do have a trans cooler mounted in front of my Radiator. And I will check under the RH tailight for the connector. Thanks for the heads up.

 

[michael loibl]

Here's a picture of the factory plastic loom leading to the factory 4 flat trailer connector. You can see where the blue wire was pulled out and then I spliced in a jumper wire which leads to my add on 7 round trailer conector. It was same blue wire as in connector under the dash. Sorry it took so long to send it, and hope you find it on yours.

 

[michael loibl]

If u still don't find it, post how many wires and what colors u have in the harness u found under the dash. I will compare it to mine for u

 

[michael loibl]

I'm trying to remember if I had to lower the spare tire out of the way to acces the harness. It's tight between the bumper and tire, but that might be because I added a 2 inch reciever below the factory 1 1/4 hitch. Good luck

 

[96firephoenix]

96firephoenix You are right on the 1.25" receiver And I am limited to 3500 lbs pull weight. My RV is 3200 lbs only 14 ft long. Though I appreciate your concern. The RV does have electric brakes though and I would like to use them when we travel in the mountains. I do have a trans cooler mounted in front of my Radiator. And I will check under the RH tailight for the connector. Thanks for the heads up.

Yea, I'd definitely use the trailer brakes in that scenario too. I pulled about 3500 unbraked weight (IN doesn't require it on older trailers) with my 02 explorer, and I wouldn't want to take that on hilly roads, let alone mountains.

I'd also be checking to make 100% sure that you have the correct auxiliary trans cooler before I attempted any mountain towing.

The 3200lb RV - that really doesn't give you much room for error on only putting 300lbs of stuff in that RV while you haul. That's about 35 gallons of water, for perspective.

I'd be looking to get a 2" receiver ASAP in your shoes. just for peace of mind.

 

[96firephoenix]

Thanks to both of you for your help.
Michael I checked the harness more than a foot and found no blue wire. I did check for voltage in the plug under the dash on the factory plug and have voltage present. So will continue checking for a connector.

This thread has a lot of info and pictures. Guy put an 04 2" hitch on an 07 explorer, has pictures of the connectors at the taillight.

 

[Ed Mountaineer]

Here's a picture of the factory plastic loom leading to the factory 4 flat trailer connector. You can see where the blue wire was pulled out and then I spliced in a jumper wire which leads to my add on 7 round trailer conector. It was same blue wire as in connector under the dash. Sorry it took so long to send it, and hope you find it on yours.

[/Hi Micheal Thanks for all your info and the great pics. As I explained before I followed the flat plug back to the right tailight and found no wires. So I verified from the Power Distribution Fuse Box, which had the fuse 30 amp number 17 for the brake wire, and the fuse 30 amp number 13 for the 12 volt trailer feed. I followed them across the front, down the firewall passenger side to a plug behind the front passenger tire attached to the frame. This plug had the blue brake and orange 12volt wires on the female side of the plug. But the male side did not have the 2 wires continuing to the back. I ran cable from here following the wiring back to the trailer and completed my connections. All runs well as I connected my brake controller and adjusted.
QUOTE]

 

[Ed Mountaineer]

Yea, I'd definitely use the trailer brakes in that scenario too. I pulled about 3500 unbraked weight (IN doesn't require it on older trailers) with my 02 explorer, and I wouldn't want to take that on hilly roads, let alone mountains.

I'd also be checking to make 100% sure that you have the correct auxiliary trans cooler before I attempted any mountain towing.

The 3200lb RV - that really doesn't give you much room for error on only putting 300lbs of stuff in that RV while you haul. That's about 35 gallons of water, for perspective.

I'd be looking to get a 2" receiver ASAP in your shoes. just for peace of mind.

Hi Fire

I will look into it though my model is the welded hitch to the frame. Not sure I can exchange it. I have completed my brake controller connections and all is working fine. Thanks for all the info.

Ed

 

[Explorer_PL]

They all are welded 06-10 but it can be cut out

 

[96firephoenix]

This thread has a lot of info and pictures. Guy put an 04 2" hitch on an 07 explorer, has pictures of the connectors at the taillight.

Hi Fire

I will look into it though my model is the welded hitch to the frame. Not sure I can exchange it. I have completed my brake controller connections and all is working fine. Thanks for all the info.

Ed

Hey, it looks like you missed my earlier post. There's a link to a thread where a guy cut off his welded 1.25" and bolted on an older 2"

Glad you got it all working though. Cue the broken record: you should reeeeally get a 2". Safety margin is a huge peace of mind, especially for mountain towing.

 

[michael loibl]

Not just for safety, but also because all the good accessories are for 2 inch hitches.
And for me, I couldn't find a big enough drop ball mount for the 1 1/4 for my tiny camper to sit level.
2 inch has much more options, and some available with the tab for a small sway control bsll

 

[michael loibl]

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