On my trailer, I've noticed that my brake controller whines and moans about the trailer unit being detected, then not detected, intermittently while going over bumps. Trailer lights flicker over bumps and brakes work intermittently then as well. Makes for some interesting grabs.
Did some investigating today and found that the issue does not appear to be related to truck or trailer wiring. Rather, it appears to be due to grounding of the trailer hitch itself.
This seems weird.
If I roll forward or backward slowly, then hit the brake hard, my trailer lights/brakes work fine. If I tow uphill, everything works fine. Other times, things are intermittent. The hitch is a turnover ball hitch, and if I pull the latch to remove the ball it will touch the truck/metal. Trailer lights come on, with some arcing at the latch/truck junction.
Is there an issue with grounding and the B&W turnover ball hitches? How can I resolve it? Have cleaned the ball/hitch of the trailer, so should have a good electrical connection there. Almost sure this is something else causing a lack of ground in the hitch.
Posted 2009-08-20 2:54 PM (#109697 - in reply to #109695) Subject: RE: Electrical Issue - DC/Vehicle
Expert
Posts: 3802
Location: Rocky Mount N.C.
Your trailer shouldn't be grounded through the hitch... It should be grounded through the trailer's electrical cable... You may want to trace out your ground wire to the trailer. Alot of times it's grounded somewhere near the trailers frame near the gooseneck hitch.
Posted 2009-08-20 3:13 PM (#109698 - in reply to #109695) Subject: RE: Electrical Issue - DC/Vehicle
Veteran
Posts: 254
Location: Dickinson, TX
I was kinda thinking the same thing, but cleaning the hitch ball/trailer receiver seemed to improve things. Disconnecting the trailer from the ball guarantees the lights won't come on.
I'll check the wiring again. I have a connector that installs into the truck's factory lighting system... not sure why it would be the issue. Will trace the ground wire. This is really aggravating.
Posted 2009-08-20 4:05 PM (#109702 - in reply to #109695) Subject: RE: Electrical Issue - DC/Vehicle
Location: Where the wind comes sweepin' down the plain...
Retento is right. Ground issue most likely on the trailer side. Need to make sure that your ground wire on your trailer is good. They will tend to corrode at the connector on the frame, or just held in place by a pop rivet and loosen up.
Posted 2009-08-20 6:31 PM (#109717 - in reply to #109702) Subject: RE: Electrical Issue - DC/Vehicle
Expert
Posts: 2957
Location: North Carolina
Originally written by Tresvolte on 2009-08-20 1:05 PM
Retento is right. Ground issue most likely on the trailer side. Need to make sure that your ground wire on your trailer is good. They will tend to corrode at the connector on the frame, or just held in place by a pop rivet and loosen up.
This is a pet peeve of mine. Any competent electrician would always use "Noalox" on any aluminum electrical connection. Yet, the trailer builders use bare rivets to make a ground. Either aluminum rivets or rivets to an aluminum skin. All should use Noalox in the connection.
Posted 2009-08-21 8:23 AM (#109761 - in reply to #109695) Subject: RE: Electrical Issue - DC/Vehicle
Elite Veteran
Posts: 801
Location: Tenn/Ala.
Mike- all of the previous advice is great. To simplify, electricity will take the easiest path. There should be a wire in your trailer plug that runs straight to the trailer frame. There should be a wire in the truck plug that runs to the battery negative. This will be the best ground. If your trailer is trying to ground through the ball, which as you've seen it can- but not well or consistently, then there is an obvious problem with the primary ground. The best way to see if you have fixed the primary ground is to hook the plug up, when the truck is not hooked to the trailer. If everything works as designed, then your ground is generally looking good. By the way- a weak ground can allow proper light operation, but will not allow enough current flow through for proper brake operation. Many complaints of weak trailer brakes have been solved by using a larger guage ground wire, often 10 ga. or so on a large coach.
Posted 2009-08-21 9:28 AM (#109764 - in reply to #109695) Subject: RE: Electrical Issue - DC/Vehicle
Veteran
Posts: 254
Location: Dickinson, TX
Many thanks, everyone, for the advice. I will have a look at things when the weather cools off a bit. I did find what appears to be a ground wire in the nose of the trailer, bolted into the sheetmetal. The wire was loose, but tightening did not fix the problem. Did not add any conductive gel or the stuff above to the connection, but at least I know where the wire is and can diagnose further at a later time.
Will get into the wiring harness as well... Probably a multitester/voltmeter would be helpful there. Will post my results back here... Thanks again!