Brake lights stay on with parking lights

Old Jan 26, 2010 | 06:26 PM
  #1  
bobfawcett's Avatar
Thread Starter
|
Member
Joined: Mar 2006
Posts: 92
Likes: 0
From: Prompton,PA.
Brake lights stay on with parking lights

I have an 05 F150 Screw FX4. Recently my brake lights started staying on when my parking lights are on. I also don't have right turn signal or flashers when my parking lights are on. The left turn signal works normal. During the daytime everything works fine. If I hold my multifunction switch up slightly like I'm going to turn right without activating the turn signal the brake lights work normal when the parking lights are on.If I turn on the flashers they just come on bright and stay that way but I do have brake lights then. Does anyone have an idea wat the problem is? Seems like the multifunction switch but I'm hoping someone may have had this problem so I'm not throwing parts at it. I tried pulling the taillight bulbs and the front turn signal bulbs and checked the wiring but still has the same issue.
 
Reply
Old Jan 26, 2010 | 07:35 PM
  #2  
SSCULLY's Avatar
Technical Article Contributor
Joined: Jun 2002
Posts: 10,511
Likes: 10
From: Under the flightpath of old ORD 22R
Try pulling the Trailer Tow adapter Stop / turn lamp fuses ( 36 & 42 I think ) and see of you still have the same problem.
 
Reply
Old Jan 26, 2010 | 07:51 PM
  #3  
bobfawcett's Avatar
Thread Starter
|
Member
Joined: Mar 2006
Posts: 92
Likes: 0
From: Prompton,PA.
Originally Posted by SSCULLY
Try pulling the Trailer Tow adapter Stop / turn lamp fuses ( 36 & 42 I think ) and see of you still have the same problem.
I will definately try this tomorrow and let you know what happens. Like I said it just started doing this all of a sudden. I hope this will narrow it down. I really don't want to buy a new signal switch but I have one ready in case I need it. Do you think that could be the problem?
 
Reply
Old Jan 28, 2010 | 07:26 AM
  #4  
bobfawcett's Avatar
Thread Starter
|
Member
Joined: Mar 2006
Posts: 92
Likes: 0
From: Prompton,PA.
It was fuse 36. Everything works normal with that fuse pulled. I searched over the wiring and my trailer plugs but I couldn't find anything unusual. Any ideas what may be the problem. I tow a couple trailers often so I'm going to need to fix this or only tow during the day I guess.
 
Reply
Old Jan 28, 2010 | 11:21 AM
  #5  
SSCULLY's Avatar
Technical Article Contributor
Joined: Jun 2002
Posts: 10,511
Likes: 10
From: Under the flightpath of old ORD 22R
This is usually caused by water, salt, etc getting into the back of the 7 pin trailer tow adapter, and causing a short in there.

Best to start with removing the adapter, and heating it to dry it out ( hang it pin facing up so the stuff drains out the back, the way it came in ), then WD-40 the snot out of it.

If this does not work, next step is to replace the 7 pin trailer tow adapter. You can DIY it at the harness behind the bumper, or pay the money to get the new Ford one, that runs up to the connector on the driver's side frame rail by the spare tire.
 

Last edited by SSCULLY; Jan 28, 2010 at 11:54 AM.
Reply


Thread Tools
Search this Thread

All times are GMT -4. The time now is 11:48 AM.