[ryano2121]

I have upfitters coming to put in my truck. I am mounting my compressor and tank now and will be wiring the compressor to one of the aux switches. I read a bunch of posts about wiring upfitters but I can't seem to get a good understanding.

I know how a relay works. On my previous compressor install, I ran the red wire from the compressor to 87 on the relay, grounded the relay at 85, powered the relay from a switched power source at 30, and connected the pressure switch on the tank to 86. The other side of the pressure switch went to switch power.

How do I wire this using the upfitters? I would assume the relay in the upfitter can handle the load, right?

 

[BXRICK]

I'll try to be generally helpful, but will lack in specifics.

How many amps does the compressor draw?
The largest upfitter switch amperage is 30 amps. If the compressor needs more than this, you'll need a second relay. If you do this, you can use one of the lower amperage upfitter switches.

If the compressor needs less than 30 amps, then you could wire it directly to the upfitter switch that supplies 30 amps. Check your owners manual, in the fuse section, for which switche(s) this is; it's changed from year to year.

Forgive me if you already know this part - someone might find it useful:
If you need to use your own relay, you'll wire the power from the switch to the the 86 terminal. Then, ground the 85 terminal.
Then, you'll supply fused battery power to the 30 terminal. Lastly, the 87 terminal goes to the compressor. Now, when the 86 terminal gets power from your switch, it will turn on the relay, closing the 30 and 87 terminals, completing the circuit, and energizing the compressor.

Also, there are four pass-through wires sort of above the brake booster. The other end of these wires is sort of above the steering wheel. They are great for getting a wire from inside the cab to outside it. You can connect the pass-through wire directly to the upfitter switch wires, which are also above the steering wheel - they actuall can touch each other with no extra wire added.

 

[ryano2121]

I have to add the pressure switch on the tank in there. This is the way the wiring diagram shows it:

Power to compressor goes to 87.

Pressure switch goes to 86 on one side and switched power on the other.

How do I do this with upfitters?

 

[Ty Pope]

I have upfitters coming to put in my truck. I am mounting my compressor and tank now and will be wiring the compressor to one of the aux switches. I read a bunch of posts about wiring upfitters but I can't seem to get a good understanding.

I know how a relay works. On my previous compressor install, I ran the red wire from the compressor to 87 on the relay, grounded the relay at 85, powered the relay from a switched power source at 30, and connected the pressure switch on the tank to 86. The other side of the pressure switch went to switch power.

How do I wire this using the upfitters? I would assume the relay in the upfitter can handle the load, right?

In my 2008 F-450, the upfitter switches had relays already installed. All I had to do was wire my compressor's hot lead to the upfitter wire. Didn't have to mess with wiring those relays (which always fail me unless they are wired right-side-up. (so water doesn't accumulate in them)

 

[ryano2121]

The upfitter switches do have relays but you can only get to the 87 terminal. I have a compressor and tank. The tank has a pressure switch that needed to be wired to the 86 terminal. So I just added a 30A relay and it works just fine. I mounted the relay under the dash so I don't have to worry about water.