Let's install the "upfitter switches"

blamkin86 · March 28, 2020

(If you've never worked on a vehicle with two batteries, let me just tell you, take all the precautions you can think of. Make certain NEITHER of your grounds can slip and contact metal. If this happens while you're working on the other side of the truck, you're in for some heartache or worse. Fire is very possible. You've been warned.)

Open the hood. Start by taking the grounds loose on both sides. Grab a 13mm socket, and while you're at it, you'll need a 10 later so grab that and an extension.

The driver's side battery ground is super easy to get to; just to the outside of the coolant bottle, right in front of the driver.

Put the bolt back in the hole, and BE SURE THE GROUND IS NOT GROUNDED. I can't stress this enough. I put the end of the ground cable up onto the overflow bottle and taped it there.

With the driver's ground zip-tied or taped to something plastic, let's move to the passenger side.

That plastic box with the red slidy thing is where we'll be working and finalizing the Upfitter Switch install.

OK... Unlike the drivers' side, the passenger side ground where it mounts to the chassis is pretty hard to get to. If you can get back there, go for it.

If not (I was not able to) then what I did was remove the metal hold down, then actually remove the ground from the terminal directly.

Here's a pic of the outer bolt on the hold down. It's a 13 as well, take it off.

If you take a close look there, you'll see I've (errantly) already remove the plastic cover from over the battery.

What could happen?

Like a complete raving dumbass, I allowed the ratchet to contact that terminal in the picture.

Don't be like me people. LEAVE THE COVER ON until you have to remove it.

Better yet, pay A LOT BETTER ATTENTION than I did.

!!BE CAREFUL!!

Once you've got the inner and outer bolt of the battery hold down off, now you can take the actual ground wire off the battery. Use your 10mm, but PLEASE BE CAREFUL. Here's a pic with the ground off the passenger battery.

No innocent bunnies were murdered, thankfully.

(Notice how far away the ground is from the battery. That's a good idea there.)

Now *you* can take the battery cover off. Yours should look like mine, only with less huge spark and arc damage on one terminal, assuming you were smart unlike me!)

Edited March 28, 2020 by blamkin86

blamkin86 · March 28, 2020

Now that grounds are off, and securely fastened out of the way, and you've unclipped the cover over the battery - you've got about 10 minutes (maybe) of stuff to do to finish this thing up.

First off, grab the pink bag that came with your kit. There's a few parts you won't need (they're for the Snowplow kit) so I didn't bother installing them. Feel free, but you'll be leaving an exposed (and fused) battery terminal open under the cover there.

Here's a pic of the parts we won't be using:

200 amp fuse, two large studs, one nut, and one custom crimped wire end with a nut on it.

Take the cover you unclipped from the battery, and turn it upside down - let's do a quick inventory of parts needed:

Flat metal plate with three holes in it

Three nuts

Three studs

60amp fuse

(the little nutsert thing isn't used, sorry it's pictured.)

Looking back at the electrical box above the battery, start counting the already-installed fuse studs from the radiator end towards the firewall. At the third stud, look just towards the passenger side in the metal plate there. You'll see a "slot" that's the same size as the three studs we have in the kit. Slip that stud into that slot - see the pic. Doesn't matter how it's oriented. The boss on the stud goes under the metal - only the threads are above it. All the studs are the same, just have at it - there's a depression there on the plastic if you need to unclip it.

(This pic is upside down, sorry - firewall at the bottom)

In the next valley over to the passenger side, you'll see two more slots in the plastic.

1) Put the two remaining small studs in those slots.

2) put the flat metal plate across the first stud and the forward stud you just added and finally

3) Lay the 60-am fuse across the two studs you put in the plastic valley

Next, and you're almost there, put the red wire we installed across the firewall on the opposite stud that's holding the fuse. Put nuts on all three studs.

At this point, test to see if your cover will go back on. Mine would not - I had to pull a little on the red wire. Be careful here, don't break anything, you may even have to go back and unclip the wire or something - I was able to lengthen it just enough to get the cover on.

Take the cover BACK off and tighten all the nuts you put on the studs (with your 10mm).

(This pic is upside down, sorry - firewall at the bottom)

Edited March 28, 2020 by blamkin86

blamkin86 · March 28, 2020

Time to put it back together.... remember your safety people. Please take it seriously.

Put the ground back on the passenger battery with the 10mm:

Put the hold down plate back on with both bolts:

Snap the cover back on...

And don't forget the driver's side ground:

blamkin86 · March 28, 2020

So... that's it.

As always:

1) Be careful with TWO big batteries. Be careful people.

2) If you have a better idea - Please share it! I did this for fun, and maybe someone will get something out of it - maybe you will also help someone else. Chime in!

3) I'm going to start a separate thing on what people are controlling with their upfitter switches.

Because I'm thinking money'll be short here soon, I'm going to just install some unused fog lights I had laying around from an old golf kart project. I need some really good loading and backup lights, and this seems like an easy/cheap first project. If I don't get laid off, I'll come back and replace these free/old lights with some $60 amazon specials (replacing my $20 amazon specials)

Enjoy!

blamkin86 · March 30, 2020

Going to add some rock and backup lights this weekend...

...here's the wire code from the upfitter fuse box

Upfitter Switch -> wire

1 -> Blue

2 -> Grey/blk

3 -> Brown/wht

4 -> Yellow/brn

They're all 14 or 12 gauge.

Edited March 30, 2020 by blamkin86

Limelight · March 31, 2020

On 3/28/2020 at 5:06 PM, blamkin86 said:

So... that's it.

As always:

1) Be careful with TWO big batteries. Be careful people.

2) If you have a better idea - Please share it! I did this for fun, and maybe someone will get something out of it - maybe you will also help someone else. Chime in!

3) I'm going to start a separate thing on what people are controlling with their upfitter switches.

Because I'm thinking money'll be short here soon, I'm going to just install some unused fog lights I had laying around from an old golf kart project. I need some really good loading and backup lights, and this seems like an easy/cheap first project. If I don't get laid off, I'll come back and replace these free/old lights with some $60 amazon specials (replacing my $20 amazon specials)

Enjoy!

I would add this from the pictures, regarding safety.

Don’t wear a watch when working around the battery if you have a metal band or bezel. It will cause the same contact arc. Your wrist won’t feel too good if it gets welded to the terminal, lol.

Actually ANY watch on your wrist is a bad idea

when working under the hood. If you need to get your hand out of there in a hurry for any reason, you don’t want that watch to hinder you’re movement....

FirstAscent · April 4, 2020

Thanks for this!!!!

Mine were installed (not wired) from the factory as well and I’ve been wanting to tackle this. Now that you did the write up I may just tackle it this weekend for some onboard air.

Thanks again!

blamkin86 · April 4, 2020

29 minutes ago, FirstAscent said:

Thanks for this!!!!

Mine were installed (not wired) from the factory as well and I’ve been wanting to tackle this. Now that you did the write up I may just tackle it this weekend for some onboard air.

Thanks again!

Very welcome!

if I did it again I could cut down to about 1/3 of the posts. Don’t be intimidated by the install you can do it.

FirstAscent · April 4, 2020

2 hours ago, blamkin86 said:

Very welcome!

if I did it again I could cut down to about 1/3 of the posts. Don’t be intimidated by the install you can do it.

Thanks, I'm fairly mechanically and electrically inclined and typically do all my own work, it doesn't looks to bad, just patience

Btw, I actually just read through everything (just skimmed through it earlier) and wanted to say great job on the write up. It was very clear and I appreciate you including your "mess up" on the terminal. Things happen, we are human, but showing that may help others to see how serious it is and to just take it easy, follow your instructions, go slow, and you'll be fine

FirstAscent · April 5, 2020

@blamkin86

I just finished wiring mine up, instructions were excellent and I now know first hand how much more it would have sucked without your help haha.

It was still a pain though.

I as well am missing two screws, this bothers me and I’ll order two more on Monday haha.

Few things I noticed during install:

1. I had a setback in the early stages. I didn’t have any factory holes on the two middle spots where the main red wire goes across the firewall, so had to drill it out. Due to the angle it was a pain in the butt.

2. Looking at your pics I couldn’t figure out how you had so much slack in your hood latch cable in order to get the knee panel pulled back so far, then I noticed afterwards a note later on where you said yours popped out of the firewall and you just had to put it back in. I ended up disconnecting the hood cable from the latch with needle nose pliers.

3. Your photo with your finger pointing where the red wire came through the firewall was helpful, I did the same as you fishing around for it. I took a photo showing the wire coming through that may or may not help others. This actually wasn’t as bad as I thought. But I probably just got lucky haha.

4. Even with disconnecting the hood latch it was a really tight fit. A short 7mm soccer would’ve helped a ton I think, I only had a long socket. It was quite frustrating.

5. You connected the red wire first to the fuse box, I connected it last after the fuse box was mounted. Mainly just so I was sure exactly how I wanted to route it.

6. You were able to pull the cable across the firewall to gain a little extra length in order to close the battery kid. My zip tie things were fairly tight on the wire so I wasn’t able to do that. I’m going to try to order new zip ties with the little mounts attached so I can readjust it. I got the kid closed but left off the last support screen thing.

7. When I turned on the truck I had an error for the parking brake. I simply pressed the parking brake button to activate it then pressed it again to turn it off and it went away.

8. When I first turned the truck on after reconnecting batteries it the DIC asked me to roll down and up the driver side window then the passenger side window. I thought that was weird but some type of calibration I’m sure. So if anyone sees that nothing to be alarmed of.

9. Super lame about not including the two bolts to mount the new fuse box. I left out two that I thought would be easiest to get to as well so I can replace them quickly and easily. Currently I left the left fuse panel off for easy access, hoping i can get replacement screws in the next few days.

10. Lastly thank you SO much for putting in the effort, it definitely helped a ton!!

Everything lights up! Now just need to connect something to it.

blamkin86 · April 6, 2020

Awesome thanks for the great update. I wonder what wire I have going across the firewall with the plastic holders on it...Also good idea on removing the hood release deal. I didn't see an obvious way to do it, although I did see the screw sticking out the back side. I guess pulling my cable out of the firewall was just dumb luck. It REALLY doesn't want to go back in, either.

And there's now at least two of us with the kit installed. I am going to post some pix this weekend of my "loading lights" I added to the rr bumper and side step.

Two screws. Not sure why they're not included. I don't mind having mine missing so I think I'm going to leave it. I hate rattles tho, so if anything starts up I'll be all over it.

Great work.

Who's next?

Major Tom · April 9, 2020

Make that three. I also ordered a 3500 AT with Upfitter switches. Did the install yesterday. The photos and instructions in this thread helped a lot. I did not take the knee bolster as far off as you did. I only pulled the first screw and clip closest to the door. I used a 1/4 inch ratchet to install the two screws mounting the fuse/relay box. This was the most time consuming part of the job. The ratchet is old and needs replacing.

Just another opinion on the extra fuse for the snow plow power. If you look under the battery cover on the drivers side there is another fuse installed, just like the passenger side battery. They are both under clipped on plastic covers and should not present a “short” hazard.

Thanks for starting the thread, the pictures and comments.

blamkin86 · April 9, 2020

13 minutes ago, Major Tom said:

Make that three. I also ordered a 3500 AT with Upfitter switches. Did the install yesterday. The photos and instructions in this thread helped a lot. I did not take the knee bolster as far off as you did. I only pulled the first screw and clip closest to the door. I used a 1/4 inch ratchet to install the two screws mounting the fuse/relay box. This was the most time consuming part of the job. The ratchet is old and needs replacing.

Just another opinion on the extra fuse for the snow plow power. If you look under the battery cover on the drivers side there is another fuse installed, just like the passenger side battery. They are both under clipped on plastic covers and should not present a “short” hazard.

Thanks for starting the thread, the pictures and comments.

Very welcome!

Very interesting on the driver side battery fuse. In my case, there's a completely empty post there, not another fuse. I in fact used that spot and added a relay and hard-wired in my camper to that spot.

So my AT is different than yours!

FirstAscent · April 9, 2020

49 minutes ago, Major Tom said:

Make that three. I also ordered a 3500 AT with Upfitter switches. Did the install yesterday. The photos and instructions in this thread helped a lot. I did not take the knee bolster as far off as you did. I only pulled the first screw and clip closest to the door. I used a 1/4 inch ratchet to install the two screws mounting the fuse/relay box. This was the most time consuming part of the job. The ratchet is old and needs replacing.

Just another opinion on the extra fuse for the snow plow power. If you look under the battery cover on the drivers side there is another fuse installed, just like the passenger side battery. They are both under clipped on plastic covers and should not present a “short” hazard.

Thanks for starting the thread, the pictures and comments.

Yeah the two screws to mount the fuse box was the worst part! haha

I wasn't able to use my 1/4" ratchet since I only had long sockets. Did you use short sockets? I was thinking it would have maybe helped if I had short sockets. Still a pain though.

Now I'm curious on what I have on my drivers side fuse, I'll have to look.

Major Tom · April 9, 2020

The 1/4 " ratchet was using what I would call a standard length socket, not a deep well socket. Still a pain to make work.

I had problems getting the hood release cable reinstalled. I pull the end of the cable out of the lever and could not get it back in. The lever is an assembly that just clips onto the knee bolster. After I figured out how to release the lever assembly, I connected the cable to the assembly and clipped it back onto the knee bolster.

Two documents that will help you, from the GM Upfitter website:

Technical Bulletin # 153 Installation of Upfitter (AUX) Switches (9L7) components Preliminary https://www.gmupfitter.com/files/media/photo/1314/UI%20Bulletin%20153_wip.pdf

Instrument Panel Knee Bolster Replacement:

https://www.gmupfitter.com/files/media/photo/1265/Instrument%20Panel%20Knee%20Bolster%20Replacement.pdf