Jump to content

Recommended Posts

Posted

Can't speak to anyone else's issue but mine (2021 Colorado with a trailer that just worked with my 2018 Silverado) ended up being a high impedance (cruddy connection) with the ground to the frame on the trailer.  Not how I would have wired the trailer originally (I'm an ****** retentive electronics tech) but instead of running the ground to each of the lamps they bonded it to the frame near the tongue and then bonded each of the lights to the nearest frame section around the trailer.  Cleaned up the first connector and viola everything works.  My suspicion is that they designed the system to "look" for a certain level of return current and if it's not there the system shuts the power off to the plug.  And now, since I have everything apart anyway, it's off to the part store for LED replacement lamps.  Hope this helps'

  • 2 months later...
Posted

I have a 2021 Z71 Suburban.  Wanted to borrow a friends trailer and plugged it in.  No lights.  Works fine on his ford.

Put in my 7  pin tester no luck.  Plugged in my 4 pin flat tester no luck.  Could not tow the trailer without lights.

Took it to Chevrolet and they showed me their tester and that all was fine.  They told me it is the trailer and asked me how old it was.  At the end they told me to take my trailers to an RV place and they would redo my trailer so it will work.  So the SMART system these engineers designed is not backward compatible on almost all trailers.  So beware.  Do not think you are going to rent a trailer that will work, borrow one from a friend or help out somebody in trouble.  I am beyond upset with Chevy.

PS  A lifter broke after 4000 miles on their most expensive and rugged suburban.  It is a known defect.  They replace all four on the right side, but would not replace the left side in spite of their being a bulletin to replace on the side if one breaks.  So now I guess I wait to break down again in the middle of nowhere Utah and then wait 5 days to have it fixed.

I think I am going to build a trailer adapter with an inline resister on each lead to make a smart to dumb adaptor.  Any suggestion of how many ohms?

Posted

Dang it.  I was set to go out and buy a 2021 3500 Silverado after having problems with my Ford.  Looks like I'd be going from the frying pan to the fire.  I guess I'll research Dodge now and see what problems they have and then pick the one with the least amount of problems.   I really liked that IFS on the Silverado one ton.

 

Posted (edited)

Make sure the 7 pin plug isn't upside down. 

 

I wouldn't have thought it was possible -- but, with at least with some trailer plugs, it is...

Edited by redwngr
  • 4 weeks later...
Posted

I believe I stumbled on the solution. I had the same issue with my 2020 Sierra. I could hook my trailer to other vehicles and the lights worked. Hook it to my Sierra, and nothing. A seven pin tester indicated no power to the receptacle (although I could see very very faint flashing of some lights on the tester). I checked every fuse and all were good. Stumped, I looked at forums for ideas... nothing worked. Then my 5 year old daughter was "helping me" and inquired about the trailer hitch icon when I placed the truck in reverse - trying to be patient, I showed her how it magnified the hitch (I don't usually use this feature). When I put the truck in park, the park brake engaged and I suddenly had all my trailering lights. The display also inquired about which trailer was connected.

 

I'm thinking it is some sort of technical setting. Back to your trailer normally and before hooking the trailer and lights use the hitch magnification feature. Hook everything up, you should now have power to the trailering plug. Ever since I started using the magnification feature, I have power to the receptacle. If I forget to use the magnification feature the lights don't work on some of my trailers, but do on others??? Simply use the magnification feature and the lights work on every trailer... go figure???!!!

  • Like 1
  • Thanks 1
Posted
On 5/12/2021 at 9:00 PM, JCRowe said:

I have a 2021 Z71 Suburban.  Wanted to borrow a friends trailer and plugged it in.  No lights.  Works fine on his ford.

Put in my 7  pin tester no luck.  Plugged in my 4 pin flat tester no luck.  Could not tow the trailer without lights.

Took it to Chevrolet and they showed me their tester and that all was fine.  They told me it is the trailer and asked me how old it was.  At the end they told me to take my trailers to an RV place and they would redo my trailer so it will work.  So the SMART system these engineers designed is not backward compatible on almost all trailers.  So beware.  Do not think you are going to rent a trailer that will work, borrow one from a friend or help out somebody in trouble.  I am beyond upset with Chevy.

PS  A lifter broke after 4000 miles on their most expensive and rugged suburban.  It is a known defect.  They replace all four on the right side, but would not replace the left side in spite of their being a bulletin to replace on the side if one breaks.  So now I guess I wait to break down again in the middle of nowhere Utah and then wait 5 days to have it fixed.

I think I am going to build a trailer adapter with an inline resister on each lead to make a smart to dumb adaptor.  Any suggestion of how many ohms?

 

I had this problem driving me crazy for two weeks smh mine ended up being fuse 74 under the hood 30amp. 2019 GMC 1500 Denali 

Posted
4 minutes ago, Fesilva said:

 

I had this problem driving me crazy for two weeks smh mine ended up being fuse 74 under the hood 30amp. 2019 GMC 1500 Denali 

 

49AD6CA7-951A-431B-BCC0-B78119B2F137.jpeg

34F01FCC-C24E-476B-B7B5-33C4EED9E6F5.jpeg

  • 1 month later...
Posted
On 5/23/2019 at 1:24 PM, P Bolton said:

Ok I hooked up a trailer to my 1 month old 2019 Chevy Silverado today for the first time and had no trailer lights. Hooked up my second trailer and also had no trailer lights. Connected both trailers to my father-in-laws truck and both worked fine. Checked both sockets the flat 4-pin and round 7-pin and had no power at either one. Anyone else had this problem?

Yes im having the same problem take a tester to the plug nothing  every time I hook a new trailer to my truck its a problem why

  • 2 weeks later...
Posted

My truck works perfect with my job trailer that’s all LED and won’t work at all with my body trailer. Just spent a week redoing the boat and it still doesn’t work. Never considered it being the brand new truck and thought I ruled that out by using my other trailer all the time. 

Posted

I have a 2021 1500 LT with issues too. No lights work at all when I plug in the 7-pin. When I turn headlights on all the running lights work, but no signals or brake lights. Any ideas?

  • 1 month later...
Posted

I have the same problem with 4 out of 5 trailers that I own, no running or tail lights on any of them when connected to my 2020 3500 HD; all the trailers worked fine on my 2015 2500 HD that I traded in and also still work on my wife's 2019 GMC SUV. I am several weeks into the Chevy senior Advisor trying to get me an answer. When is GM going to acknowledge there is a design flaw that needs to be corrected, it can't be that 90% of the trailers being used are incompatible with the advanced trailering system, designed by GM?

  • 6 months later...
Posted

Have a 22 3500. I have 4 trailers with brakes, a '90 Titan that has had led bulbs installed, a '09 ADS seed tender w/ incandescent, '21 and a '22 H&H with leds.

 

No problem with any light issues, but issuse recalling the brake gain after shutting down the truck and restarting. Something like Error, can not recall brake gain. Check brake gain. It's always correct as to the adjustment, that I have set for that particular trailer.

 

DIC came up once with Check Trailer Right Turn Signal Lamp. Had a bad bulb. I like the system so far.

 

I also dislike not being able to choose the correct trailer while in gear or moving. It defaults to guest trailer. 

Posted

You are having luck than me. I have hooked up six different trailers and have problems with everyone. It goes from everything fine to no trailer connected to check a specific light to trailer connected in many different sequences. Dealer has no clue because it is hard to diagnose an intermittent problem. I think this falls on GM to give them some guidance. 

  • 4 weeks later...
Posted

Good morning.  I have a brand new 2022 Rockwood trailer and I get no running lights (no power to my backup camera either) when I hook up my 2019 AT4.  If I manually turn on the head lights, the running lights now will work.  Sounds like I need to go to the dealer with this issue and get nowhere like the rest you, right?

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
  • Forum Statistics

    250.5k
    Total Topics
    2.7m
    Total Posts
  • Member Statistics

    342,914
    Total Members
    8,960
    Most Online
    AidenVorpagel
    Newest Member
    AidenVorpagel
    Joined
  • Who's Online   3 Members, 0 Anonymous, 1,284 Guests (See full list)


  • Latest Articles

  • Posts

    • 286,740 Mile Services   8/6/2026   New AC Compressor. Refrigerant oil and dye, evacuate and charge system.  New exhaust system from cat back.  New Iridium plugs plus replace #3 coil Repair/rewire headlamp wiring (passenger side) and replace all forward bulbs. Polish lenses of both assemblies.  Pull rear rotors, clean and adjust parking assembly. Inspect, clean and grease front calipers. Check pads and shoes.  4 wheel power bleed of brake system. Dot 4 Reset idle speed 50 rpm higher New Serpentine belt.    Will need new pads in the rear in about 5K more miles.    Tax Title and License out the door just short of a grand.    AC clutch had bitten the dust. 1 year warranty on the pick and save replacement. Thing will make a Polar Bear cry Uncle.  He spent quite some time on the wiring. It was in the harness and he does nothing half. I got off cheap. I have considerable more light down the road. Sylvania Silver Star replacements.  Gas seal between the porcelain and shell of plug #3 was blown, cooked the coil. That was the cold miss.  Love the new exhaust. I can sneak into the neighborhood again.  Nice to have a working parking brake again. Belle Tire never got it done. That was disappointing.    This was one of her bigger bills and still way cheaper than a payment even given the oil consumption. This thing cost me under a hundred a month in repairs and normal routine costs. What is my incentive to replace it? 🤔           
    • hello I recently bought a 2012 gmc 1500 with a 5.3 and have a AFM disabler on it I'm interested in doing a cam but I'm worried if I remove the AFM system I will fail smog does anyone have info if they are able to detect that or a work around to it (not talking about hot smogging) please let me know thank you  
    • Update. I started chasing down my symptoms. Started first with pulling valve covers and looked at everything. Everything looked good and couldn't hear or feel anything different. Then a compression test. 240 psi or really close on each cylinder. I was worried I was a tooth off of timing. Not bad for an engine with 173,000. Granted I did put new heads on. I sprayed water around the injector area to see if I could hear a change. Nothing. I hooked up my new hp tuner which I should have done in the first place but I don't really know what I'm looking at just yet but am learning. I noticed the fuel trims were way off so that told me I have to have either a bad injector or exhaust leak. New injectors, so I did the shop vac on blower and in the tail pipe. Sprayed soapy water and found the exhaust flange on the drivers side was leaking. I didn't think it would be that considereding I pulled the heads and left the manifolds attached. I did have the transmission replaced not long ago. They must have not seated them properly but I guess I didn't notice. I put in new gaskets on both sides. Which by the way isn't a bad job but I had a hard time getting them to seal right. Took two attempts. Reset the fuel trims and the ticking is gone, engine runs smooth and acceleration has improved. Got to feel the real difference with that stage 1 cam. It's not that big of a difference but it does add a little more. It feels like how the truck should have been from the factory.
    • Can it still be Assembled I?    Stribeck says that we need a certain amount of viscosity under conditions of load and velocity to prevent two surfaces of a know roughness from tearing each other asunder. And we have marketing trying to tell the masses that those two surfaced require less of that commodity due to more exact limits being placed on the same old clearances. We also know that there are limits to how hard something can before it becomes to brittle to be viable and to smooth to 'wet' the surface and that both of those conditions have been known and met since about the Second World War.    That viscosity value shook out at 10 centistokes at 212 F just under a hundred years ago.  Give this a look: [Anton Parr]     What is advertised is the Kinematic viscosity (mm2/s) or that which has been density adjusted but the value we are after is the dynamic viscosity (mPa.s) or true viscosity. You can see that this number is dependent on density thus base stock and temperature. You can also see that an SAE 30 doesn't reach that value in this example. However an SAE 30 that is at the upper end of the SAE 30 range; 12.5 cSt (mm2/s), might. 12.5 * .83 = 10.375 (mm2/s). If you could find an SAE 30 at the upper end these days.   Then there is the complication of viscosity modifiers or VII or VM, whatever you wish to call them. Polymers added to very thin base oils, perhaps 3 to 6 cP oils, that will meet the SAE *W30 spec at 'tested' shear rates and 100 C/212F  target temperature. So a polymer fortified base that is a fraction of the 10 cP requirement Stribeck insist upon.   This could be all well and good if those polymers didn't have two very problematic 'features'. They shear or loose viscosity both 1.) permanently and 2.) temporality. And they do both omitted in the advertised data with the distinct  purpose of deceiving the consumer of the actual operating state of the fluid. I've shown the example of Warren Oils COSTCO 10.91 cSt 5W30 formuation several times where the 100 C HTHS value is 6.9 cP!! That's the temporary shear down and with and SSI or shear stability index of 9.4 cSt. Note the intentional deception in using mixed units?    After a short while that 9.4 cSt oil has a viscosity corrected dynamic value of 7.8 cP. But as the SSI is still within the range of an SAE *W30 whose lower value is 9.3 cSt.    This allows them to continue to call this SAE 16 weight oil a 30 weight, the cake, and still meet the API requirements for fuel efficiency IMPROVEMENT mandated by the EPA. The eating of the cake. By the time you've worn out your motor doing the responsible thing by adhering to the warranty requirements, (the stick), you get deprived of the carrot, wear control. So sad, to bad.   So what can be done? Do I need actually say? [Anton Parr]       Even this must be monitored if the oil is on the low side and the VII an organic or you opt for a 0W40 with an even lighter base oil and more / higher MW VII. (Note the lower density of the 40 weight versus the SAE 30 mono-weight?)    There is another workaround. Temperature. An SAE *W30 run at a bulk temperature of between 180 and 195 F.    Being the belt and suspenders sort I am I do both. Run it cook and run it heavy.    In Part II I'll work the AW package. 
  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...