Payton34

I received the gen5 harness and it looks like they shipped the wrong one. The part I ordered 250430 was supposed to be the redisgned harness that looks like Van's harness but I think I got a Sle to Slt harness. Now have to wait till tomorrow for them to call me back

I didn't notice mine flickered for a few days until I was behind another truck and the reflection on their tailgate showed the flickering. There could be others out there with a flicker but never noticed because it goes away after 5-10 min of driving. I have gone through everything checking all possable problem areas. There are no cut wires, ground is working, battery and alternator are good. I had a theory the driver side only does it maybe because it is a much shorter distance from the fuse block and maybe.

Yes he is having the exact same issue as I am. Driver side flicker only when turn signal is on and then once truck warms up everything works ok.

It only flickers if truck has sat atleast 3-4 hours or longer. I do not have dual batteries I will have to see what alternator it has.

I will find out when I get mine today. It is a redesigned harness for 14-15 SLT to 16 SLT headlights so I just hope it works.

That one is for SLE trucks which do not have factory LED DRL. The SLE used the low beam as the DRL and I thought that harness canceled out the low beam drl and had to pull from the battery for DRL since factory wiring didn't have separate power pin for DRL.

They do not have the one that draws power from the battery any more. They redesigned it http://www.gen5diy.com/GMC/Sierra/P-P-Harnesses7/20142015-GMC-Sierra-SLT-to-2016-GMC-Sierra-12-Ton-LED-Headlight-Harness/

I ordered a Gen5 harness and will have it today. I will see if there are 2 capacitors in the wiring.

Horacio and my truck are 6.2 and have flicker so maybe the electrical system has a more irregular voltage until they warm up

I actually prefer the look of DRL staying on. I was wondering if trucks with the 6.2 are only effected by the flickering drl until it warms up.

Yes the drl only flickers when just the drls are on and the turn signal is used. Once truck warms up it works normal

I thought there was something wrong with my truck since no one else had this issue but I guess the harness needs a capacitor for the drl too. I wonder why some trucks don't have this issue. Wonder if it depends on options or the engine size.

I tried the number 6 and all other fuses labeled BCM but didn't change anything.

Plugged stock headlight in and the drl doesn't flicker with the turn signal so I have ruled out the truck wiring, and the driver side Led headlight is ok when plugged into passenger side so the housing are not the problem

I am going to plug the stock headlamp back in to see if the drl flickers. I am positive I never saw it flicker before I removed them but I am actually hoping it does because then the dealer will have to fix whatever is wrong under warranty. I tested the ground and it is working so it does seem the power between the drl and turn signal are crossing some how but only if the truck is cold. If I turn on the parking lamps or headlights when the truck is cold the drl doesn't flicker with turn signal. The hard part is testing all the possibilities I have a limited window to try things. Once truck is warmed up everything is ok and I have to wait for it to cool down a few hours.

What is this cap? is it the headlight housing of part of the harness? Also wouldn't this issue be occuring on both side of the truck if there was irregular voltage.

I have been looking through upfitter guide to see if one of the relays in the fuse block X50A controls turn signal or DRL. I used to have a HID kit with the stock headlights and the relay on the HID harness would stick sometimes and I had to replace a couple times. This is the only explanation I can think of that would make the DRL flicker only when truck is cold. Anyone now if a relay exists under hood or in the instrument panel fuse blocks?

I really have no idea anymore its only the driver side with this issue. I am going to look through the factory harness for any cut insulation on the turn signal and drl wires but the fact everything works ok after about 10 minutes of driving baffles me. If there was a short with wires it should be happening all the time. I really have no idea anymore its only the driver side with this issue. I am going to look through the factory harness for any cut insulation on the turn signal and drl wires but the fact everything works ok after about 10 minutes of driving baffles me. If there was a short with wires it should be happening all the time.

I just emailed GEN5 to see if they know of a pin design change from 2016 to 2017 headlamp parts.

I dont have multi meter but could get one. I was just looking up part#s and GM has a few differnt parts for the LED left hand side headlight a couple parts show discontinued. Maybe they changed the pins on the housing? I am going to try reach down and take pics of pins https://www.gmpartsonline.net/auto-parts/2016/gmc/sierra-1500/slt-trim/6-2l-v8-gas-engine/electrical-cat/headlamp-components-scat

This makes sense what is happening once the turn signal illuminates the drl goes off for a second then back on. It slike when the turn signal goes on it is taking power from the drl. The weird thing is it happens every morning when the truck is cold and after driving 5-15 min it functions normal. It has never gone more than 10-15 minutes of the flickering. I was thinking if there is a relay maybe it is sticking until it heats up? I just disconnected plug again and used electrical cleaner and made sure there was nothing in the plug pins blew compressed air and applied dielectric grease and reconnected. I though the plug maybe wasn't fully connected and power was jumping pins but then it would continue to flicker even after the truck is warmed up. Whatever is going on it has to be temperature related

I have the seals and used dielectric grease. Maybe I will put more grease in