20gmctruckguy

I think you made a good choice! I chose GMC as well just because of the look of the front end.

That's quite the story! Glad you finally got your new truck. Big step up from the Ridgeline. You should put a tiny red pin stripe on it in memory of the poor hawk.

I tried mine today and it seems to be working and our outside temperature is only around -7 C. Maybe mine does not have the thermostat? It's a Duramax.

Can you post a pic of the positive and negative cables from the lightbar that you said you disconnected? Not sure why there would even be any. How many wires or pins are in the plug that is closest to the actual light bar? I'm thinking there should only be 3. One for full power, another for ground and the third to control the low power feature. There shouldn't be any need for more wires going to the battery if you are connecting to the gm upfitter switches by the steering wheel. The gm upfitter switches have relays built in.

I'm starting to wonder if you might have disconnected a ground wire by mistake. Earlier on you mentioned disconnecting the main power wires from the light bar and then had no power. Battery should be fine if it shows 12.4 with engine off. Reconnecting the light bar wires might be giving just enough ground for most electrical things to come to life but not enough for the starter. Check the ground cables wherever you have been working. A light bar just cannot provide power because it is not a battery.

Looks like the voltages are spot on. I checked mine today just for my own curiosity and had 12.4 and 14.6. So even with your light bar disconnected the truck will not start without the jump box assist? That is strange, and all I can think is to take the truck to a good mechanic. Maybe the cable to the starter is loose, but not too likely.

Okay, do the same test on another car battery if you have one around. That will confirm the multimeter is working.

Yes, that's the toold you need. Set the dial 3 clicks to the left (on the 20) which should read up to 20 volts DC. Put the black wire probe into the bottom hole and the red one into the hole directly above it. Black is negative (-) red is positive (+). Touch the probes to the corresponding battery posts and see what reading you get. Not sure if your multimeter needs a battery, but probably make sure it has a fresh one in it.

It's quite possible for you to have a faulty battery. It happens quite often. Have you got a volt meter that you can see how many volts the battery is putting out? Shold be around 12.4 without the engine running and around 14 with engine running.

Just thought of something else. Did you move the 5 amp fuse in the upfitter relay box to the "switched" side? Mine came with the two 5 amp fuses install in the constant power position. When in the switched position there will no power to the accessories when the truck is off.

That's much easier to see! It looks like the green wire needs to be connected to ground via a seperate switch. It's like they are intending to take power "away" from the light in order for it to be in "low mode". I would suggest connecting the white wire to switch #1 and then install a seperate toggle switch into the green wire and then to ground (probably ground to the same spot as the black wire). You only need to connect to ONE of your upfitter switches. Hope this works for you.

Can you post a picture showing the intructions and diagram from Baja Designs. I can't zoom in enough without making it blurry! Don't connect the green wire to any of the upfitter switches. I'm thinking that might be a mistake but want to see the instructions more clearly.

I realized my mistake later and have edited it. #1 & #4 are 30 amps.

Did some research and I find that switches 2 & 3 are both 20 amp circuits. Switches 1 & 4 are 30 amp. Switch #1 is the blue wire number 965 and switch #4 is the yellow/brown wire number 968. Again, use a test light to confirm. The green wire confuses me. It looks like it goes through a switch and then to ground. If that's the case, then it should not go through the upfitter switches. Can you post a better picture of the wire diagram from Baja?

I'd like to try to help, but not sure if my ideas will be good oe bad. First thing is I don't think you should require any extra relays as the up fitter switches already have them built in. One for each switch. The wires coming out from the upfitter switches are fused as you know and supply positive power to whatever accessories you w ant to connect to them. Try connecting a test light to the wire you are connecting to and make sure it is properly controled by the aux switch you intend to use. In your post you didn't mention where you connected the white wire. You did say that you connected the black wire to wire 966 (grey/black) using a quick slice Baja Designs supplied and then later that you attached black to ground. Just need to confirm where the black is actually connected, because it shouldn't be connected to any switch wires. I'm not able too see the wire numbers in your attached pics, but will go get my print outs to double check which wire comes from which switch.