For some reason my z axis not disabling when not in use during prints and is overheating. This has caused it to start moving down, instead of up for each layer of a print and has torn up a couple hot ends.

Can anyone point me towards code in the firmware or anywhere else so that I can identify what should be disabling the Z?

I'm working with ReplicatorG, Gen3 Electronics.

Thanks.

Even if it is not disabling, it should not be over heating. I recommend turning down the potentiometer so that it stays cooler.

If you are using the standard 5D firmware, something to keep in mind is that many settings are broken out by motherboard type. When you change a setting, you need to look at the "if define MOTHERBOARD" lines to make sure that you are editing settings that relate to your motherboard.

It almost sounds like you accidentally changed the setting that inverts the axis instead of the one that disables an inactive axis as well, so just double check that.