Notices
JK Electrical, Lighting & Sound Systems Bulletin board forum regarding topics such as stereo head units, CD players, MP3 players, speaker systems, amplifiers, hardmounted GPS devices, computers, headlight upgrades, fog lights, off-road lights, general wiring and anti-theft devices.

4 pin vs 7 pin trailer harness

Thread Tools
 
Old 07-24-2011, 04:05 PM
  #1  
JK Junkie
Thread Starter
 
xerofall's Avatar
 
Join Date: Jul 2008
Location: Tooele (two-willa), Utah
Posts: 2,088
Likes: 0
Received 2 Likes on 2 Posts
Default 4 pin vs 7 pin trailer harness

I've been wonering what more a 7 pin powers than a 4 pin. My new trailer only has two tail lights but has a 7 pin plug and was wondering why.
Old 07-24-2011, 04:07 PM
  #2  
JK Enthusiast
 
Skid_Kid's Avatar
 
Join Date: Jul 2011
Location: Ca
Posts: 358
Likes: 0
Received 0 Likes on 0 Posts
Default

Here you go.

Click image for larger version

Name:	7WayTrailerEnd.jpg
Views:	14005
Size:	28.4 KB
ID:	185560
Old 07-24-2011, 04:16 PM
  #3  
JK Junkie

 
OH9JK's Avatar
 
Join Date: Jan 2010
Location: Stokesdale, NC
Posts: 3,796
Received 3 Likes on 3 Posts
Default

Originally Posted by xerofall
I've been wonering what more a 7 pin powers than a 4 pin. My new trailer only has two tail lights but has a 7 pin plug and was wondering why.
Mostly used for trailers with electric brakes.
Old 07-24-2011, 04:45 PM
  #4  
JK Enthusiast
 
remingtonJK's Avatar
 
Join Date: Nov 2009
Location: Cabot, AR
Posts: 262
Likes: 0
Received 0 Likes on 0 Posts
Default

My boat has a surge break on it. In order for you to back it up you need a five wire plug. I installed a 7 pin connector and used an adaptor for it. The 5th wire releases the brake when your in reverse.
Old 07-24-2011, 04:56 PM
  #5  
JK Super Freak
 
Freewill's Avatar
 
Join Date: Jun 2011
Location: Olympia, WA
Posts: 1,715
Likes: 0
Received 11 Likes on 11 Posts
Default

The extra pins cover whatever you need. For trailers, that is usually electric brakes. There can also be an "always on" 12volt feed that keeps the trailer battery charged.

The 7 pin is also useful when you tow the Jeep. Same basic setup: 4 wires for left/right/run/ground. 3 more for brakes, 12V charge, and a spare.
Old 07-24-2011, 06:35 PM
  #6  
JK Junkie
Thread Starter
 
xerofall's Avatar
 
Join Date: Jul 2008
Location: Tooele (two-willa), Utah
Posts: 2,088
Likes: 0
Received 2 Likes on 2 Posts
Default

The 4 pin to 7 pin adapter I bought has two bullet connection wires coming off the loom and a white (ground) loop. Since my trailer doesn't have electric brakes I could probably run something else to the trailer, like bright rear lights, etc...



Quick Reply: 4 pin vs 7 pin trailer harness



All times are GMT -8. The time now is 11:15 AM.