Ender 5 Pro With CR Ouch V BIGTREETECH-SKR-mini-E3-V2 and BIGTREETECH TFT35 Touch Screen “Failed to Enable Bed Levelling” Workaround

So after spending an evening upgrading my Ender 5 Pro with a CR Touch (not the BL Touch) with a BIGTREETECH-SKR-mini-E3-V2, a BIGTREETECH TFT35 touch screen and a BTT Smart Filament Sensor following the video by Kersey Fabrications Youtube videos BIGTREETECH TFT35 V3.0 on your Ender 5 Plus Parts 1-3. I flashed his firmware onto my printer, remember mine is an Ender 5 Pro, this has a point later on.

BTT Firmware

JST XH 2.54 mm 2 Pin Male and Female Connectors

KATSU Solder Seal Wire Connectors 50PCs, Waterproof Heat Shrink Butt Connectors Cable Sleeves, Electrical Wire Terminals Insulated Butt Splices for Marine Automotive 312700

I had a day to myself and began to start up the printer.

The first issue was that the BIGTREETECH (BTT) TFT35 showed that there was "No printer attached".

This was a simple fix by going to Teaching Tech’s video BTT TFT35 dual mode touch screen guide at 7:30 minutes in.

That sorted. Now to the real issue at hand for this Instructables.

On the Void Lab Discord channel, I posted the following

“When I start up the Ender 5 pro, I get the message Failed to enable bed levelling. I understand that I need to level the bed and do something to the mesh but cannot work out how. I have searched but cannot find a simple read-through/ or video on how to do this. “

This LINK takes you to the start of the thread.

Now I’m not going to bore you with all the various things that were tried but in essence, what I was trying to do was get the bed to Home then do a Bed Level.

In essence, the bed would drop down and the CR Touch would deploy and I'd get the error message "Failed to enable bed levelling"

This is where the CR Touch wiring comes into play.

Because of the way that the CR Touch is wired it throws up a couple of problems for it to work with BTT firmware for the SKR-mini-E3-V2 for the Ender 5 Pro and I suspect with the other Ender printers taking this upgrade.

The CR Touch wiring needs some emendation for this project. This has one (1) 5-pin connector, whereas the BL Touch has two (2) connectors. One is a 3-pin connector and the other is a 2-pin connector.

So the video next shows the CR Touch and hot end looking to Auto Bed Level. The bed is not rising to the CR Touch but dropping on the Z-Axis and the error messages displayed on the TFT35 were "Stop called because of BL Touch Error - Restart with M999" and "Home Z first"

This is because I had disconnected the physical Endstop at both ends as this was described as a step in installing the CR Touch when it was connected to the original Creality 4.2.2 Silent Mainboard fitted when I purchased my ender 5 Pro.

The BTT board would appear to need them connected. So, I reconnected both ends of the Z end stop to their respective sockets on the switch and the board.

I ran the Home process and here's what now happens after connecting the Z Endstops.

Then picking up on @xneme's comment on Discord here is the position and type of wiring that the CR Touch has connected to the board. I'd attached the 5-pin plug to the Z Probe. This is partly right as the Yellow, Black and White wires are required in this position.

The Blue and Red require moving. But before we go there I must talk about my Big Mistake

It was also noticed that my Printer was not Homing to the centre of the build plate. 

WARNING MESSAGE

This turned out to be as mentioned at the beginning of this Instructable to be an important issue. 

I said at the start I had FLASHED Kersey Fabrications Ender 5 Plus firmware and when carrying out the bed levelling caused the X-Axis to crash into the front left of the printer because mine is an Ender 5 Pro.

The Build plate for mine is 220 x 220 and the Plus is 350x350. Fortunately, it did not cause any damage. 

So at this stage of your Upgrade use the official BTT Firmware. When I find another more up-to-date firmware I'll put a Link in here.

Moving on.... Step 6

I removed the red and black wires and pins. You need to be careful, sometimes the lip thingy gets pushed in a bit, but you can carefully lift it back up. You just need a pin to get the contacts out.

Now, pull out red and blue wires from the CR Touch Board Connector, using JST XH 2.54 mm 2 Pin Male Connector

1. Red goes where the black one was in the 2 pin
2. Blue goes where the red one was.

If this is too much for you, as it very nearly was for me, you could, using KATSU Solder Seal Wire Connectors 50PCs, Waterproof Heat Shrink Butt Connectors Cable Sleeves, Electrical Wire Terminals Insulated Butt Splices for Marine Automotive 312700

This video shows how they can be used. Adam Savage's Quick Electronics Wiring Tips!

I used a lighter to join wires together.

Now as an aside later when I put the bottom cover on the Mainboard the blue wire came loose so using a hot-glue gun I secured both the Red and Blue wires into the JST XH 2.54 mm 2 Pin Male Connector and plugged it back in.

After that, it was fairly straightforward levelling the bed and mesh. 

I apologise if this is a bit long-winded but that is just my way of explaining things. I hope you are able to get my point.

If you have any problems please give me a ping via email and I’ll do my best to assist you.

All the links are for illustrative purposes I am not clever enough to work out monetisation.

Trickyhicky