It’s a 2-way communication path over the 7-way plug. The truck brake controller also monitors current to know if your turn-signal bulbs are working, etc…
Well, I’ve personally received a few dozen emails about this over the last several months, so it must be a problem. And many (most) new RVs are offering solar panels as an option. I hope GM pays attention and issues a real fix, since it will only get worse as more trailers have solar panels and lithium batteries.
Mike, I’ve had this exact issue with my 2020 and now my 2024, both 2500 HD. After seeing the bulletin, I added a switch to be able to turn off the solar panels while driving and this has worked. Question: is there a way to limit the voltage at the 7-way to 13 or so volts?
Hey Mike. Really enjoy your site. What if you install a small agm battery hooked up to the truck’s positive wire and not to the trailer’s. Then the solar wouldn’t be in the circuit. Just a thought. Also, my truck shows 14 volts from the alternator all the time.
I have a 2016 Jayco Fifth Wheel, I tow with a 2015 GMC Sierra 2500 HD. This same issue started about 3 years ago while towing. “Check trailer connection” when this happens you have no trailer brakes,the manual trailer brake slide also dosent work! Dosent happen all the time either,but what’s puzzling is I’ve had this happen with no trailer connected! The visiual& audio warning, sometimes from 5-10 min.then clears up. I’ve taken it to the dealer they plug in a tester to both my bed plug and the bumper plug. Of course everything. Checks out ok,so I just live with it & hope it dosent happen when I towing and coming to an emergency stop!
Mike the problem solutions from GM are BS. I have a 2015 1500 GMC and have the same problem but I have the problem so this is ongoing with them. I have the same problem when not connected to any trailer at all. So checking for solution on the trailer end does nothing to cure a problem that is clearly on the truck end. GM just will not stand up and admit any problem on their end.
It’s a 2-way communication path over the 7-way plug. The truck brake controller also monitors current to know if your turn-signal bulbs are working, etc…
Well, I’ve personally received a few dozen emails about this over the last several months, so it must be a problem. And many (most) new RVs are offering solar panels as an option. I hope GM pays attention and issues a real fix, since it will only get worse as more trailers have solar panels and lithium batteries.
On my trailer, I have the 12VDC pin disconnected form the truck. When I buy my 2024 GMC 2500, I am going to do the same exact thing
Sorry, not within a days drive of Maryland. We are in Southeast Michigan. If we weren’t leaving warmer weather, I would meet you half way.
Mike, I’ve had this exact issue with my 2020 and now my 2024, both 2500 HD. After seeing the bulletin, I added a switch to be able to turn off the solar panels while driving and this has worked. Question: is there a way to limit the voltage at the 7-way to 13 or so volts?
Where are you located?
Hey Mike. Really enjoy your site. What if you install a small agm battery hooked up to the truck’s positive wire and not to the trailer’s. Then the solar wouldn’t be in the circuit. Just a thought. Also, my truck shows 14 volts from the alternator all the time.
Hey Mike
I have a 2016 Jayco Fifth Wheel, I tow with a 2015 GMC Sierra 2500 HD. This same issue started about 3 years ago while towing. “Check trailer connection” when this happens you have no trailer brakes,the manual trailer brake slide also dosent work! Dosent happen all the time either,but what’s puzzling is I’ve had this happen with no trailer connected! The visiual& audio warning, sometimes from 5-10 min.then clears up. I’ve taken it to the dealer they plug in a tester to both my bed plug and the bumper plug. Of course everything. Checks out ok,so I just live with it & hope it dosent happen when I towing and coming to an emergency stop!
Mike the problem solutions from GM are BS. I have a 2015 1500 GMC and have the same problem but I have the problem so this is ongoing with them. I have the same problem when not connected to any trailer at all. So checking for solution on the trailer end does nothing to cure a problem that is clearly on the truck end. GM just will not stand up and admit any problem on their end.
Mike, if voltage is a problem, why not have a DC to DC transformer that would keep the volts in range.
Can that many RV'ers have solar panels that this is a major issue?
It only takes one heavy trailer with brake failure to cause a catastrophic accident.