Jump to content

Trailer lights flashing

plbass
 Share

Recommended Posts

plbass New Member

plbass

Posted
Posted

I have a 2020 GMC Sierra xlt. Whenever I park my boat trailer and turn off truck the trailer LED tail lights flash every 10 seconds. Any ideas on what is causing this?

JJ461 Enthusiast

JJ461

Posted
Posted (edited)

This is normal, it is stated in the owners manual on page 312.

 

"When a trailer is connected and the ignition is off, the Trailering App System will periodically pulse
the lighting circuits of the trailer to verify it is still connected. The trailer lights may periodically flash as a result of this trailer connection detection. These flashes may be more visible in dark ambient light environments. The flashing or flickering lights are a normal condition and the Trailering App System has built-in protections to prevent the battery from draining. When Theft Alert is also enabled
the frequency and pattern of this flashing will change."

Edited by JJ461
  • Like 1
  • Thanks 1
Mudcon Enthusiast

Mudcon

Posted
Posted

Yea mine does it too, it is the truck making sure the trailer is still connected. 

  • Like 1
SVG Enthusiast

SVG

Posted
Posted

Completely normal as stated above. First time I saw it happening I thought WTF??

SVG Enthusiast

SVG

Posted
Posted (edited)
10 hours ago, Chris Callanan said:

I've seen reports of folks with dead batteries in the morning though - so I unplug the trailer overnight just in case :)

I don't have any current facts to back up my position at the moment but I'd be shocked if the trailer monitoring system draws that much power to make a good battery discharge that much.

 

One thing to remember, there is a trailer alarm setting that will set off the alarm if someone disconnects your trailer, presumably in an attempt to steal it.

Edited by SVG
  • Like 2
JJ461 Enthusiast

JJ461

Posted
Posted
On 10/7/2021 at 10:19 AM, SVG said:

I don't have any current facts to back up my position at the moment but I'd be shocked if the trailer monitoring system draws that much power to make a good battery discharge that much.

 

One thing to remember, there is a trailer alarm setting that will set off the alarm if someone disconnects your trailer, presumably in an attempt to steal it.

This is a feature I found out that the truck had at about 10:00 one night when I decided to unplug the trailer after the truck was locked... BTW the key fob was in the house, wasn't popular with the neighbors that night.

  • Like 2
  • Thanks 1
Tmb New Member

Tmb

Posted
Posted

I, too, have this situation with my 2019 Chevrolet Silverado. When my truck is turned off, the trailer lights on my horse trailer continue to flicker repeatedly every 10-15 seconds forever. I’ve resorted to unplugging the trailer to avoid any draw on my battery. 
NEW: I read not to long ago on this forum site that GM had come up with a fix. Some type of new computer module? My Chevy dealership had never heard of it so I had to furnish them the #specs from the Forum article I had read. It’s as yet, not a formal recall. Anyone know any more news on this issue?

SVG Enthusiast

SVG

Posted
Posted

Here is the page from my 2021 owners manual that talks about the trailer sensing. It says there is battery management software to protect the battery from discharging.

 

Maybe earlier year trucks don't have this feature? Not sure.

 

 

2021-gmc-sierra-1500-owners-manual copy.pdf

  • Like 1
Mudcon Enthusiast

Mudcon

Posted
Posted
On 10/7/2021 at 11:19 AM, SVG said:

I don't have any current facts to back up my position at the moment but I'd be shocked if the trailer monitoring system draws that much power to make a good battery discharge that much.

 

One thing to remember, there is a trailer alarm setting that will set off the alarm if someone disconnects your trailer, presumably in an attempt to steal it.

I have left mine plugged in for a week on vacation without cranking my truck at all and did not have a problem with it cranking.  It was nice to have them flash as extra security to let people know or possibly think it might be armed and not try and steal it.  We were riding atvs and from top of the mountain at night I could see my truck flash down where it was parked. Pretty neat. 

  • Like 1
carlosh Enthusiast

carlosh

Posted
Posted
On 10/12/2021 at 1:15 PM, Tmb said:

I, too, have this situation with my 2019 Chevrolet Silverado. When my truck is turned off, the trailer lights on my horse trailer continue to flicker repeatedly every 10-15 seconds forever. I’ve resorted to unplugging the trailer to avoid any draw on my battery. 
NEW: I read not to long ago on this forum site that GM had come up with a fix. Some type of new computer module? My Chevy dealership had never heard of it so I had to furnish them the #specs from the Forum article I had read. It’s as yet, not a formal recall. Anyone know any more news on this issue?

They performed the tsb and plug fix on mine. Now lights only flicker on every 45 minutes or so

Mike_F Enthusiast

Mike_F

Posted
Posted
Quote

They performed the tsb and plug fix on mine. Now lights only flicker on every 45 minutes or so

carlosh

 

Do you have the numbers for the TSB and plug fix.

 

My dealer is clueless or lazy or maybe both, but definitely useless at this point.

 

Thanks

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
 Share
Go to topic listing

  • Latest Articles

  • Posts

    • Chuck FB
      Correct way to service 2024 l8t allison trans?

      By Chuck FB · Posted

      Thanks for that, yes just because I could I measured what came out just to give me some guidance although I already knew to expect it to take at least 9.5 to just throwing in the whole 10 quarts off the shot and doing a one and done heat cycle to drop out the excess to get to the proper level. I don't recall exactly now what I measured that came out but was less than I put back in, I knew I spilled some on the garage floor but the main part was that I was thrilled in the discovery I did not have to touch my exhaust to flex it down. The gasket manipulating is a pain of course to create that clearance to take the pan out and put back in but its all very doable if one is careful and not forcing the gasket to flex too much. From the quote I got at a transmission shop of 900.00 here in Canada ( never asked at the dealer what they charge ) I saved 700.00 doing it myself after paying for the supplies so that to me paid very good wages !, and I knew what fluid was put in and that I had changed the filter and that the level is correct without any doubts. 
    • bojanglespa
      2016 Sierra 1500 6.2L lifter Failure 🤨

      By bojanglespa · Posted

      I do have one of the AFM diasable box, using it for last 1.5 years.
    • Mellowth
      Tonneau cover and rack combo

      By Mellowth · Posted

      I found a setup that lets me open the cover partway with racks installed, using side-rail-mounted systems for easy access.
    • Chuck FB
      first oil change - 2026 2500HD gas

      By Chuck FB · Posted

      Typically its said and I agree so far that the engine oil drain plug oring is not required to be changed out unless you see some damage happening to the oring as apparently the oring lasts well. The dealer I have been getting a few parts from never even stocked the oring but instead stocked the whole drain plug that comes with a new oring which for the dealer is easier because they just throw in a new drain plug if there was any question about damage on it as well and charge the customer accordingly but again only if it is needed.    Also a hint about the drain plug oring to help it last vs a risk of causing damage to it, after its been removed and wiped off or washed off ( that is a whole other topic about some solvents damaging orings because some solvent types do ) to make sure to relube the oring with a bit of new oil so that it won't "grip" on the sealing surface of the pan and needlessly stress out the oring. Its no different than putting some oil on the sealing ring of the engine oil filter. So I just grabbed a new drain plug to have on hand although more recently bought just the oring as well but as its special it costs half the price of the drain plug ... !   Since you mentioned the hate to be empty handed theme, I am not sure what you have in the way of filter removal tools as I like using the exact sized for the filter steel 1" wide band with side to side swivel handle filter removal tool, and it can be used to snug up the filter without risk of damaging a filter as well ( its probably a lisle brand I have ). The drain plug hex size is 15mm and I always like using a 6 point socket if I have a choice and with this truck I've been using just a 3/8 ratchet that has a fairly long handle. Do you have a funnel that will work to pour oil in as that is definitely the short coming bastard part about the design with that fill port on the valve cover on such an angle that no normal funnel will even work. There are adapters and things on the market that will set into or screw into that fill port, I didn't want to deal with US shipping as that is all I was seeing at the time so caved and bought a Lisle brand multi vehicle fit adapter funnel kit and it really works well but there are much less expensive adapters out there that work in conjunction with an off the shelf funnel that would do the job also. Now that I have it, I like how it works and works so slick with the shape of the Amsoil 1 quart containers I have now switched over to. Whatever you do, have a funnel system of some sort as you will be swearing if you dropped the oil and then realize you have nothing to properly pour new oil in without spilling it all over the engine !.     Other comments, quite a bit of oil flows out down the filter when its cracked loose due to the housing above the filter so let it dribble down the filter until it slacks off flow and then remove the filter to create less possible mess. It seems these engines can sit for quite a while and drip and if you have time let it sit there and drip out of the engine as much as it wants. Also a good time to grease the 9 zerks on the front end, that's my typical practice anyway to grease the suspension and steering each time I change the oil. And remember to reset the oil change minder ( not something I am used to doing with older vehicles and equipment ). 
    • Aimatdeer
      Correct way to service 2024 l8t allison trans?

      By Aimatdeer · Posted

      I really did not measure what came out. I carefully followed directions to check level after i did the spill and fill and filter change. I used 10 quarts. 9 was not quite enough. My trans temp was about 175 when I checked it. Truck sitting in my driveway very close to level where I always check oil pretty much every time for consistency. My driveway is just ever so slightly downhill to run water to the street.

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...