2024 Silverado 3500 Upfitter Switches

kf9yr · September 7, 2023

The fusebox for the upfitter switches should be installed just above the driver's side knee panel.

Poke your head under the dashboard and it's pretty much in line with the brake pedal, a small rectangular plastic box.

The output wires are pretty short but you will find them there. Read the bulletin and there is a way to make the outputs always available or only when the ignition key is on.

I didn't take any pictures with my 2020 so none to share with you.

One of the switches is wired to work with a light for snowplowing / towing /etc. It runs up near the center mounted third brake light.

Good Luck!

MesaRat · September 7, 2023

2 hours ago, kf9yr said:

The fusebox for the upfitter switches should be installed just above the driver's side knee panel.

Poke your head under the dashboard and it's pretty much in line with the brake pedal, a small rectangular plastic box.

The output wires are pretty short but you will find them there. Read the bulletin and there is a way to make the outputs always available or only when the ignition key is on.

I didn't take any pictures with my 2020 so none to share with you.

One of the switches is wired to work with a light for snowplowing / towing /etc. It runs up near the center mounted third brake light.

Good Luck!

Thanks. Too tired to look today but will in the morning. I thought the leads would be in the engine compartment. I guess I have to wire through the firewall to get to the front bumper and it looks like the existing pass through is already used for the up fitter wiring.

Brent85224 · January 9

Do we have any upfitter switches for the 24 ultimates yet? Really needing them.

kf9yr · January 22

I have a 24 AT4 with the same dash layout as the ultimates…

I installed a Garmin Powerswitch in the engine compartment instead of waiting for the upfitter switches.

It’s expensive but if you download the app you can switch the powerswitch from your dash with Apple or Android carplay…

Another plus is the wires are out of the passenger compartment if you’re switching external lighting / accessories.

rjgvt · January 22

I didn’t see the upfitter option when I ordered my AT4 in October. Picked up my truck 3 days ago and found the upfitter harness in a bag under the back seat. Thought it was kind of odd to have the harness and no switches on the dash.

Kerry Pulaski · February 6

As @kf9yr mentioned, the Garmin kit is much better install in my view, than the GM OEM 9L7, and so is the AuxBeam AR-800. And still there is no Upfitter Update for the AT4/Denali Dash Swithces to be available.

Reason....Garmin & Auxbeam...ALL connections are under the Hood for the devices to control, and just one has to go thru the Firewall.

The GM 9L7, ALL device connections have to go thru the Firewall to the Relay Box under the dash. A real PITA to pull thru.

And these two aftermarket ones have WIFI off your phone as well, the 9L7 does not.

I wasted so many brain cells in 9L7 research, and replies from GM Tech, that the Kit "is coming" for At4 and Denali.

After seeing how much a PITA it is just to hook up 12v thru the firewall, for a Subwoofer I added, Naaaaa. I'm going with the Auxbeam. They have several units for capacity needed.

See a You Tube from "Don's Life", on his AT4 Auxbeam install. That convinced me. It's better organized that the GM 9L7.

After so much time in and under the dash, adding cabin foot lighting, and mute sounding Bose speakers etc., I'm done. Time to enjoy this new mortgage payment.

Kerry Pulaski · February 6

On 1/9/2024 at 12:43 AM, Brent85224 said:

Do we have any upfitter switches for the 24 ultimates yet? Really needing them.

Brent, I just added my comments at the end, just now. I addition, I just checked today 2/6/24, the Gm Upfitter page, for the 9L7 Upfitter Install #3 for At4 & At4X, Denali and Ult. will NOT be available till 2025 units released !

Kerry Pulaski · February 6

On 1/21/2024 at 9:07 PM, rjgvt said:

I didn’t see the upfitter option when I ordered my AT4 in October. Picked up my truck 3 days ago and found the upfitter harness in a bag under the back seat. Thought it was kind of odd to have the harness and no switches on the dash.

@rjgvt, see my comments added. #193C Upfitter notice on the 9L7 for AT4 & X, Denali & Ult, NOT available till 2025. This would be the difficult final design of the dash switch Cluster, is the hold up. The WT work truck and other standard dashboards, could use existing switch "pods" for the '23 & '24. Not Denali, Denali Ult, and At4, At4X, dash re-fresh designs.

Kerry Pulaski · February 6

On 1/9/2024 at 12:43 AM, Brent85224 said:

Do we have any upfitter switches for the 24 ultimates yet? Really needing them.

Look at the Garmin and Auxbeam products for 9L7 capability.

chopjaw · February 8

On 2/6/2024 at 2:48 PM, Kerry Pulaski said:

Look at the Garmin and Auxbeam products for 9L7 capability.

I was told they can be ordered and put in a build for all GM 2024 2500/3500 trucks. When I was building an ultimate at the stealership it was offered on the 24. I just could not bring myself to buy a $112K truck. I just couldn't... So I got a 2k used 3500HD High country for $82K instead. Here is the photo that salesman took of my switches.

Edited February 8 by chopjaw

gemarsh · February 8

2 hours ago, chopjaw said:

I was told they can be ordered and put in a build for all GM 2024 2500/3500 trucks. When I was building an ultimate at the stealership it was offered on the 24. I just could not bring myself to buy a $112K truck. I just couldn't... So I got a 2k used 3500HD High country for $82K instead. Here is the photo that salesman took of my switches.

That's the problem, different dashes. Anything GMC AT4 and up on the refresh, has a different dash layout.

Pryme · February 8

11 minutes ago, gemarsh said:

That's the problem, different dashes. Anything GMC AT4 and up on the refresh, has a different dash layout.

Ok since all you electronic gurus are posting here I’ll ask you guys to identify all of this. My truck came with all of this stuff and it also already has the upfitter buttons in the dash.

how easy or hard would it be to set up?

thanks!

gemarsh · February 9

2 hours ago, Pryme said:

Ok since all you electronic gurus are posting here I’ll ask you guys to identify all of this. My truck came with all of this stuff and it also already has the upfitter buttons in the dash.

how easy or hard would it be to set up?

thanks!

The bag is zip ties.

gemarsh · February 9

Seriously, the item on the left is is the underhood wiring harness from battery fuse block, 2nd is the fusebox for the switches mounted under dash going to a loose connector under dash and the switches, 3rd I'm not familiar with.