GM Upfitter Switch install issue

[Winnie2020]

I tried this install over the weekend in a 2022 Chevy 2500. Everything went according to the numerous videos and instructions on the net.


The aux buttons light up when the headlights are on and then when each button is turned on, the small yellow bar on each button lights up. I tested power where the main upfitter power cable ties into the electrical system and we're good.


The upfitter switch fuse box that is a part of the install is defaulted to provide power when the truck is running which is how I did my testing. However, I don't have any power coming to the 4 wire bundle where you would tie in your accessories. The 5th button goes with a wire that dead ends at the upper brake light for a strobe.



I first used a volt meter and got nothing. I thought maybe I had a grounding issue so I tried a simple circuit tester with a long ground wire running all the way to the battery and nothing there either (I tested the ground wire and the tester at the battery and the ground wire was good).



If the panel with the 4 aux lights lights up, it seems to me I have power.



However, I'm at a loss for what to do next.



Any ideas?

[Mic]

Originally Posted by Winnie2020

I tried this install over the weekend in a 2022 Chevy 2500. Everything went according to the numerous videos and instructions on the net.


The aux buttons light up when the headlights are on and then when each button is turned on, the small yellow bar on each button lights up. I tested power where the main upfitter power cable ties into the electrical system and we're good.


The upfitter switch fuse box that is a part of the install is defaulted to provide power when the truck is running which is how I did my testing. However, I don't have any power coming to the 4 wire bundle where you would tie in your accessories. The 5th button goes with a wire that dead ends at the upper brake light for a strobe.



I first used a volt meter and got nothing. I thought maybe I had a grounding issue so I tried a simple circuit tester with a long ground wire running all the way to the battery and nothing there either (I tested the ground wire and the tester at the battery and the ground wire was good).



If the panel with the 4 aux lights lights up, it seems to me I have power.



However, I'm at a loss for what to do next.



Any ideas?

have you tried adding a load to see if it detects it

[Winnie2020]

Originally Posted by Mic

have you tried adding a load to see if it detects it

Ah! So you're thinking the aux fuse box assembly was designed so that no load is passed unless a load is detected? I'll rig something up to test that.

[Skillet173]

Not sure exactly how it works seeing as my 22 hasn't yet been built. but I did watch a few videos so I will have an idea when it gets here.
I'm assuming you wired the power from the 30 amp post on battery also? Maybe the switches pick up power from the under dash OEM "clip" for backlighting? Really just a guess.

[CampNBrew2]

Watching this as I have a 22 GMC on order with the upfitter switches.
I have seen on the forums people finding they inadvertently forgot to replug a connector.
I also think you can change the type of power to the switches based on fuse location- Key switched to Acc or Engine Running. Have you tested power to the respective fuses and relays in the box, in and out? I would start here and work outwards.
Good luck and please do share any findings or tips.

[Skillet173]

Originally Posted by CampNBrew2

Watching this as I have a 22 GMC on order with the upfitter switches.
I have seen on the forums people finding they inadvertently forgot to replug a connector.
I also think you can change the type of power to the switches based on fuse location- Key switched to Acc or Engine Running. Have you tested power to the respective fuses and relays in the box, in and out? I would start here and work outwards.
Good luck and please do share any findings or tips.

Any word on when to expect it? My order is in signature and there’s no word on tpw.

Sorry,Don’t want to hijack thread, just curious.

[CampNBrew2]

Originally Posted by Skillet173

Any word on when to expect it? My order is in signature and there’s no word on tpw.

Sorry,Don’t want to hijack thread, just curious.

Ha I was going to ask you the same- if you got any kind of info. I ordered mine 11/5/21. All they could tell me was "an average of 8-16 weeks". I am hoping to get a build date or something soon. Not holding my breath. Plus I ordered a double cab which I understand they stopped making for awhile. Crazy times.

[Winnie2020]

Originally Posted by Mic

have you tried adding a load to see if it detects it

Just wired up a brake light as a test load and nothing. It baffles me. The aux buttons light up with the headlights and then again when I actually turn them on.



I think I can pull off the bolster that covers the fuse box and then drop the fuse box to get access behind the panel to check connections without having to take apart the dash again....arrrggghhh.

[Mic]

Originally Posted by Winnie2020

Just wired up a brake light as a test load and nothing. It baffles me. The aux buttons light up with the headlights and then again when I actually turn them on.



I think I can pull off the bolster that covers the fuse box and then drop the fuse box to get access behind the panel to check connections without having to take apart the dash again....arrrggghhh.

I would check power to ground at the switch to start with...then trace out the wires.

[Mic]

Originally Posted by Mic

I would check power to ground at the switch to start with...then trace out the wires.

from what I saw /read on interweb



did you install teh fuses in the under hood fuse box?



apparently the switch LED power is NOT the load power..it is switched through a contactor.

[Skillet173]

That’s also the way I understand it. End user (because spending 1.5 tons of money isn’t enough��) must run a 30a fuse and wire from battery box to passenger compartment and the switches.

[Winnie2020]

Originally Posted by Mic

from what I saw /read on interweb



did you install teh fuses in the under hood fuse box?



apparently the switch LED power is NOT the load power..it is switched through a contactor.

I sure did and put a volt meter on the power cable at the load side and have power up front under the hood. It could made sense that the switch LED power is drawn from the other pin connector that's part of the set up. I am going to get back into the dash this weekend and start tracing from the power cable.

[ChuckS]

You might want to spend a bit of time on this link and check out the bulletins and such regarding Upfitter buttons on MG trucks...

https://www.gmupfitter.com/technical-bulletins/

[Winnie2020]

Based on posts in other forums, I went back to check the power cable that passes through the fire wall and how that cable connected to the fuse box wiring harness. Other posts on other forums have indicated problems with the cable not seating correctly in the fitting which was my issue.


My suggestion for anyone else trying this:



In the parts kit, there is a gray connector that is loose in the kit. The power cable is meant to be inserted (on the correct side) in this fitting first and then the fitting inserted into gray plug wired into the fuse box harness. My mistake was first plugging in the fitting to the gray plug without first inserting the power cable into the fitting that was loose in the parts kit.



I've attached the only pic I found on the net with the gray fitting circled in green and then a green arrow to the place on the harness where the gray fitting would be inserted.



Be sure you use the correct side.

[CampNBrew2]

Glad you found it!
And thanks for the detailed info @Winnie2020, definitely saving this for later.

So what are you running from your switches? Mine (someday) will all likely be Aux/Work lights.

[Skillet173]

Originally Posted by CampNBrew2

Glad you found it!
And thanks for the detailed info @Winnie2020, definitely saving this for later.

So what are you running from your switches? Mine (someday) will all likely be Aux/Work lights.

^^^^ Yes, what he said!
Seems like most of the time the problem is rectified but the solution is not posted!

[Winnie2020]

Originally Posted by CampNBrew2

Glad you found it!
And thanks for the detailed info @Winnie2020, definitely saving this for later.

So what are you running from your switches? Mine (someday) will all likely be Aux/Work lights.

At first a radio...we'll see what next after that.