TAZ 4/5 To TAZ 6 Differences In Wiring

I structurally upgraded the my two TAZ 4’s to TAZ 6’s; however I still need to complete the additional wiring to the RAMBO board. I found a picture of the TAZ 6 RAMBO wiring here: http://devel.lulzbot.com/TAZ/Olive/production_docs/OHAI/03_ControlBoxWiring-OHAI-T6.pdf

Looking at the RAMBO boards on my TAZ 4’s it looks like there are only four connection areas that are different and I drew red rectangular boxes around those four areas as shown here:

Are those four connection areas the only differences in the wiring between the TAZ 4/5 and the TAZ 6? Also, I assume the X, Y and Z Max connections (Box 1) get attached to the three corresponding limit switches and the 5v fan gets connected where I drew Box 4; however I’m wondering what the other two connection areas (Box 2 & 3) get connected to. Any ideas?

Box 2 is the return wire for the bed leveling pad leveling system. And the other one may be the nozzle leveling wire to the hotend. I may also have them reversed. The assembly guide is here:


Cool, do you know if those 4 red rectangular boxes show the only differences in wiring between the 4/5 and the 6?

Red Box 2 has two wires, one that connects to EL-HR0087 and the other EL-HR0081 (whatever that means). I’d rather not create new harnesses for wires that are already good to go, so I’m just trying to wire the new connections created for the TAZ 6.

Does anyone know if the two Red Box 2 wires get connected to the new z min button switch mounted on the side of the bed?

Those are the only differences in the Rambo connections. The power supply connection is a litlte different to accomodate the light up power switch, and some of the internal control box wires are different lengths. There is a document showing all the wireing harness layouts and plugs somewhere in devel.lulzbot.com or download.lulzbot.com. That should give you a picture of what those named cable assemblies consist of.

No, those are the connections to the aluminum Bed plate and the sense wire on the nozzle. :nerd:

If I remember off the top of my head right the bed switch is going to the Z min connector, but it is best to read the OHAI for that one.

Cool, do you know what red box 3 is for?

I’m aware of the TAZ 6 Wire Assemblies document:


However it’s not really clear to me which wire goes where on the RAMBO board. I wish I could find a good schematic with a cross reference showing which wire attaches to where on the RAMBO board and where it attaches on the TAZ 6 printer.

It is where the blower fan for the second extruder connects.