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"Check Trailer Wiring" Solution?

blackedout96
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blackedout96 Enthusiast

blackedout96

Posted
Posted

I've had this issue now with two new trucks. The first a 2014 Silverado 1500 and now my 2016 Sierra Denali. Any trailer I ever connected them to I constantly get the "trailer connected" message followed by "check trailer wiring".

 

I'd love to blame the problem on trailer wiring, but the same trailers function perfectly when connected to Ford trucks and older GM's. This isn't an intermittent, works on some trailers not on others thing. Neither truck has ever cosistently operated the brakes on any trailer properly.

 

I've never seen a recall or GM acknowledgement of the issue, just wondering if anyone has ever found any solution.

bdbake01 Senior Enthusiast

bdbake01

Posted
Posted

Curious myself. I have the same issue.  When it happens, the brakes stop functioning until I turn the truck off and back on.  Not cool. 

badge171 Enthusiast

badge171

Posted
Posted

Bad ground somewhere in the trailer. Some trailer's the ball will make the ground circuit. Not so, needs a dedicated ground on the trailer, The lighter the ground wiring diameter gauge. The weaker ground is produced.  

MySilverado180 Enthusiast

MySilverado180

Posted
Posted

I have had this issue on multiple occasions towing an RV. The 7 way connector is a very loose fitting, and when it loses connection, I get this error message on the DIC. Always have to re-seat connector and turn vehicle completely off to get it to reset.

 

Tried electrical tape to make it a tighter fitting. Worked better, but not great. Found that I had to tap  the 7 way in further by a little less than 1/2 inch. It then grabbed properly and no more issues. Very tight fit when I did that, was almost afraid of breaking something. 

 

Thanks for the TSB link above. I will also try getting the Pollak connector.

avgas Enthusiast

avgas

Posted
Posted

For some reason people who wire trailer plugs do not think they need to connect the ground wire. The ball just doesn't provide a good enough ground. Check the trailer ground, Its likely the issue. 

blackedout96 Enthusiast

blackedout96

Posted
  • Author
Posted

Ordered a Pollak plug for my trailer, we'll see if that helps.

The frustrating part for me is that I pull customers' trailers frequently and I can't go changing their plugs for the one time I tow them. I also have a 2014 F-150 for my shop truck and that operates all of them properly every time. I just have to use my personal truck when that's busy, which is most of the time.

The problem is so widespread and well known that GM must simply have no interest in fixing it. If Ford's 7-ways are forgiving enough to work on all trailers without special provisions, then GM should seriously consider trying a new style plug.

  • 1 year later...
donaldbailey New Member

donaldbailey

Posted
Posted

my 2018 gmc is doing the ….. check trailer wiring  …...trailer connected ...on dash display 

trailer brakes don't work when check trailer wiring comes on 

 

GMC put on new truck reciprocal  didn't help 

I changed trailer plug... twice 

I ran separate ground from  trailer to truck 

still does it

 

trailer works fine on other peoples gmc truck 

 

any ideas would be appericated 

 

 

MySilverado180 Enthusiast

MySilverado180

Posted
Posted

I also had similar issues and even had the dealer look at it. Everything was working correctly according to GM. Also noticed the loose fitting plug. Seemed too loose to maintain electrical connections. So I looked inside the receptacle and if you look closely you can see what looks like a quarter round piece of trim between the base and the wall. I figured my plug was going just above this, keeping it loose.  Next time I towed, I had to push really hard to get the plug to seat inside that quarter round.  It did! The plug was now tight, and never had the problem again. If you do this, just make sure the plug is aligned with the pins correctly and should be 95% of the way in, still loose fitting. That last 1/8 of inch is the push really hard part.

 

good luck.  

kenny_r Enthusiast

kenny_r

Posted
Posted

My truck does the same thing...2017 hd. There is just enough play on the trailer side connection that it triggers the message. Sometimes you can bend the tabs on the female/trailer side and it will work. That was the case with mine at least.

donaldbailey New Member

donaldbailey

Posted
Posted

Thank you i will look at that 

i hooked a tarp strap to plug yesterday seemed to help but still does it 

 

going to measure today to see if it is going into socket all the way 

 

i will look at bending tabs 

also ordered a different plug for trailer ...one thar somebody suggested

i do appreciate all the ideas 

  • 5 months later...

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