Five pin harness on trailer- four pin on Pathfinder.

[RobTX]

Hi all-

Trailer has surge brakes; what to do?

 

[Silvertip]

You have two choices:
1) Do nothing. The four pin connector will mate with the five pin on the trailer. The down side is that the reversing solenoid on the trailer won't work and the brakes will lock up when you attempt to back up (especially up a grade or over an obstacle).
2) Add the back-up light wire and a five pin connector to the truck. When in reverse the reversing solenoid will now work and the trailer brakes won't actuate when you back up.

 

[ihearth2o]

I thought they made 4 to 5 pin adapters. COuld be wrong.

 

[MRS]

Are the wire colours white green yellow and brown and brown with yellow strip?

 

[H20Rat]

You don't need an adapter, there is nothing to adapt to. As silver mentioned, the 5 pin trailer harness will fit perfectly in the 4 pin vehicle harness. No adapter in the world will make up for the lack of the reverse light wire.

 

[ihearth2o]

The adapter I saw came with a reverse wire. Definitely not a plug and play like a 7-5 adapter but only had to splice into the reverse wire. The "adapter" part plugged right into the existing 4 pole plug and the other end was a 5 pole plug. Link is below. I don't remember them being that expensive but I thought they were cheaper than that even. Might wanna shop around a little.

http://www.etrailer.com/Wiring/Tow-Ready/20036.html

 

[RobTX]

Watched that video - -my vehicle is a Pathfinder, vehicle is a year newer xTerra..should be close enough. Thanks for the tip. With all the hills etc in the Hill Country of TX I don't want to have the reverse solenoid kicking in. BTW...anyone know how I could positively identify the solenoid?

 

[oldjeep]

Watched that video - -my vehicle is a Pathfinder, vehicle is a year newer xTerra..should be close enough. Thanks for the tip. With all the hills etc in the Hill Country of TX I don't want to have the reverse solenoid kicking in. BTW...anyone know how I could positively identify the solenoid?

The reverse solenoid will not be "kicking in" Its only fuction is to lock out the brakes when you put the vehicle in reverse (assuming you have the wiring to turn the thing on). Even actuators with a solenoid usually have the manual lockout wedge so that you can manually lock out the brakes to go into reverse. (All my trailers do)

 

[RobTX]

Sorry Jeep- not sure I'm following you here. I wire the 5 pin adapter to my reverse light, thus energizing the blue wire when reversing; this in turn energizes the solenoid (what I was referring to as 'kicking in"), which effectively prevents hydraulic pressure from reaching the brakes, allowing me to back up with the trailer. Do I have this right or am I misunderstanding something?

 

[smokeonthewater]

yes that's right... BUT......DON'T bother with any adapter.... The hassle and cost of hooking up said adapter would be worse than just installing the 5 wire plug.

The wired on your plug are as follows... the metal exposed pin is the ground... the first after it is tail lights... the next two are turn signals/brake lights... the fifth one is the brake lock out..... Either add the correct plug and run one wire to the backup light circuit or just plug it in and go..... If you do the latter and get in a bind trying to back up you can unplug the trailer and turn the plug sideways... plug the 5th terminal (lock out) of the trailer end into the second terminal (tail lights) of the vehicle end, then turn on your lights ... this will energize the solenoid and you should get enough of a ground through the hitch ball to be able to back up.

 

[oldjeep]

Sorry Jeep- not sure I'm following you here. I wire the 5 pin adapter to my reverse light, thus energizing the blue wire when reversing; this in turn energizes the solenoid (what I was referring to as 'kicking in"), which effectively prevents hydraulic pressure from reaching the brakes, allowing me to back up with the trailer. Do I have this right or am I misunderstanding something?

That is correct

This statement is the one I was responding to - makes no sense
"With all the hills etc in the Hill Country of TX I don't want to have the reverse solenoid kicking in"

 

[ihearth2o]

yes that's right... BUT......DON'T bother with any adapter.... The hassle and cost of hooking up said adapter would be worse than just installing the 5 wire plug.

It costs $12.99. As for the hassle, it would actually be easier to install because instead of splicing and rewiring all the leads, you just have to splice into the reverse wire, but hey if you wanna save a few more bucks and do a little extra work, then who am I to say.

 

[oldjeep]

It costs $12.99. As for the hassle, it would actually be easier to install because instead of splicing and rewiring all the leads, you just have to splice into the reverse wire, but hey if you wanna save a few more bucks and do a little extra work, then who am I to say.

Most vehicles wouldn't be a splice and rewire - just buy the correct plug in harness, unplug the old and plug in the new. Sure it'll cost you $40 but then you don't have to deal with cobbling into the factory harnesses. Best way is usually to get the 7 pin vehicle kit and then you are set for any type of trailer by just running an adapter plug in the 7 pin.

 

[bruceb58]

Best way is usually to get the 7 pin vehicle kit and then you are set for any type of trailer by just running an adapter plug in the 7 pin.

That's what I would do. All my vehicles use the 7 pin and I use the 7 pin on my Wellcraft trailer.

 

[oldjeep]

That's what I would do. All my vehicles use the 7 pin and I use the 7 pin on my Wellcraft trailer.

Most of mine are 7, but I've got a 4 also built into the truck and a 7 to 5 for when I have to tow my father in laws boat.

 

[smokeonthewater]

7 rv won't have backup lights... you will have to splice that one

 

[bruceb58]

7 rv won't have backup lights... you will have to splice that one

Usually the center pin is used for reverse.

 

[oldjeep]

7 rv won't have backup lights... you will have to splice that one

sure does. Otherwise the backup lights and solenoid on my trailer are operated by magic. 7 pin factory wiring in the truck and trailers.

Good chart here
http://www.hopkinstowingsolutions.com/support/wiring-guides.html

 

[smokeonthewater]

hmmmmmm well I guess ya got me there... For some reason I couldn't open any hopkins web page but I looked on etrailer and there it was... the center lug is listed optional reverse... sooo I'll change my statement to:
7 way rv MAY not have reverse and you MAY have to wire that part OR it MAY have it..... I am certain there is no reverse light in my rv plugs but my stuff is custom wired by me with two rv plugs (one in the bed) and a class 8 (semi) plug.... I have always considered the center lug on the rv to be aux for whatever you wanted it to be but then I've never owned a trailer w back up lights or electric surge lockout...... I guess it could still be used for other stuff but wouldn't be universal then.....

I'm planning on wiring my fifth wheel with led work/backup lights all around and using that lug with a toggle switch on the dash..... I guess it'll still be sorta universal.....

You have me curious now... I'll check the plug n play outlet on my dad's 98 chev 1500 and the factory outlet on my bud's 03 dodge dually.

Further I'll see if the extra wire is in the (7 rv) pigtail on my big boat trailer..... work/backup/landing lights would be cool for it too

EDIT: upon looking a little further I found several diagrams that listed it as I had remembered as "auxiliary" so it may be a crapshoot as to what vehicle would have it wired as reverse lights OR it MAY be an old truck vs new truck thing....... either way THANKS for pointing it out... I sorta learned something today lol

 

[oldjeep]

The last 3 trucks I've had were wired for reverse. 2 fords and a dodge.