Truck bed lighting

[19sierra53]

Ive seen a '20 hd with a utility trailer hooked up lights flash every 10seconds or so while the truck was off and no key fob in truck. Nothing on the truck itself, just the trailer lights. Not sure why the trailer plug power has this, or if this ever stops after a certain amount of time or something

[Ryno12]

For some reason my LED bed lights that i installed flash every 5 or so seconds when my running lights are off (they are wired to be on when the running lights are on).
I wired them with a CURT 56584 wiring harness to avoid cutting or splicing any factory wiring harness and used the running light wire and ground to power the LED bed lights.
When I switch them on with the running lights on they also flash about 7 times then they finally power on normally.  Does anyone have an idea why they would flash? 
 

Looks like the running light source has some monitor/power activity even when powered off.  Guess I will have to run power for the bed lights to the 7 way 12v constant and just remember to turn off the switch when not in use.  Either that or run them constant with a relay to the factory bed lights.

Yeah, I’ve read about that before in other threads & have seen it happen with my truck & trailer. I was told it had something to do with the trailer theft setting but I shut it off on mine & it still does it.
You’ll likely have to wire it to the 12v constant. You could maybe wire in a switch so the light shuts off when the tailgate is closed.

[Troger]

3 hours ago, Ryno12 said:

 

Yeah, I’ve read about that before in other threads & have seen it happen with my truck & trailer. I was told it had something to do with the trailer theft setting but I shut it off on mine & it still does it.
You’ll likely have to wire it to the 12v constant. You could maybe wire in a switch so the light shuts off when the tailgate is closed.

 

Thanks Ryno12 for the information I have never heard of this.  I just turned it off in the trailer settings and now the lights don't flicker or flash at all when off.  Either I got lucky or it was fixed with one of the recall/software updates.  Anyhow thanks again.

[Ryno12]

Thanks Ryno12 for the information I have never heard of this.  I just turned it off in the trailer settings and now the lights don't flicker or flash at all when off.  Either I got lucky or it was fixed with one of the recall/software updates.  Anyhow thanks again.

Glad to hear it worked out for you. I’ll have to play with mine a little more to see if I can get them to stop flicking.

[Troger]

51 minutes ago, Ryno12 said:

Glad to hear it worked out for you. I’ll have to play with mine a little more to see if I can get them to stop flicking.

Well after turning off the trailer notification last night I got in the truck this morning and the screen showed lane change alert disabled and says I have trailer lights that are out.  I unhooked everything and finally got the truck to clear the errors.  Looks like I will go with the other plan to wire directly to 12V and not play with fire anymore.

[Ryno12]

Well after turning off the trailer notification last night I got in the truck this morning and the screen showed lane change alert disabled and says I have trailer lights that are out.  I unhooked everything and finally got the truck to clear the errors.  Looks like I will go with the other plan to wire directly to 12V and not play with fire anymore.

If I recall, there’s an accessory setting for the trailer plug. I wonder if that might work better for your application.

[Coles5515]

Anyone find a viable solution to adding more lights? Is there a way to splice a switch into the current bed lights? 
 

Can the oem lights be popped off even with a spray in liner? Figure that would be the easiet is just run them off those lights...

[Hotwheel]

I assume the blue wire in the factory harness for the box lights goes to the BCM, is the a way to tap that wire to the BCM in the cab so when the interior lights come on when you open the door or hit the unlock button on the fob the bed lights would also come on? 

[ravend]

I plan to use the tailgate release circuit to trigger a relay and have the bed lights come on and stay on for a period of time. Hoping to grab 12v for the relay from the lighting circuit in the rear.  Using one of these adjustable timer relays. (ive used them before and they are great) https://www.amazon.com/dp/B07JC38GLS/ref=cm_sw_em_r_mt_dp_2SM8Y740QSXPHX2VNJVJ

 

If you have a bed cover  and dont mind your bed lights on all the time...you could use a diode and pig tail at the bcm plug to jump headlights to bed lights. So bed lights are always on when the headlights are on.

[dieseldick]

I have a 2021 1500 sierra at4. Put a set of 3 led running lights on and tapped off the trailer running light wire. Well these new trucks are too smart. The truck can sense these lights and assumes a trailer is hooked up. From there, it thinks the other trailer lights are not working and warns you constantly. It also makes the side cameras come on when using the turn signals. I'm looking to see if hooking into the tail light parking lights might eliminate this issue.

 

After I posted, I realize my profile is a bit outdated. I had since had a 2018 high country 6.2 and now have the sierra AT4 6.2

Edited April 7, 2021 by dieseldick

[Michael Louis]

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Edited February 11, 2023 by Michael Louis

[wepiii]

Maybe I just got lucky but I just ran mine directly from each bed light and have had no issues. They just come on with the bed lights and go off with the bed lights. I used ttaps or whatever they are called and went straight to the bed light wires.

[Fla Eagle]

On 2/24/2020 at 6:06 PM, ILSilverado said:

Yea or how about one in the bed?

I added a switch in the bed that works the same as the switch in the cab.

 

https://www.gm-trucks.com/forums/topic/260999-20225-cargo-bed-lights-secondary-switch/

[Fla Eagle]

On 8/29/2020 at 8:06 PM, Coles5515 said:

Anyone find a viable solution to adding more lights? Is there a way to splice a switch into the current bed lights? 
 

Can the oem lights be popped off even with a spray in liner? Figure that would be the easiet is just run them off those lights...

 

On 2/23/2020 at 6:23 PM, HONDABBQ said:

It does seem a little silly to have to go in the truck to hit that light switch to turn them on long term. 

 

You can add a switch to the bed. Here's what I did on the refresh.