CR touch not deploying

Ender Series General Discussions
1

A few years ago, I was gifted a Creality Ender 3, I have since upgraded the main board to 4.2.7 and added a CR touch. Recently, I discovered I hadn’t been using the CR touch correctly.

When I try and deploy the CR touch, it doesn’t deploy. I did have another CR touch which wouldn’t let me turn the machine on. I have since discovered that the ground pin was touching the +5V pin on the CR touch end. When I tried to start the ender with that CR touch, it just wouldn’t turn, hence I am a little concerned that I have damaged the board somehow.

So the question is, have I fried my main board, I have a Creality 4.2.7 board.

When start the machine, instead of deploying as it should on start, it just lights up red, when I try and deploy manually, it’s just red.

I am wondering if I need to get a new board.

Any help is appreciated.

2

Did you check the fuse on the main board? 4.2.x boards have a fuse on them, just to the side of the incoming power wires. It’s a blue 15 amp micro-fuse, similar to what’s in cars today. You can pull it out and replace it.

3

The main board is working as expected. If the fuse had gone it wouldn’t even turn on.

I have tried anothe CR touch, another main board, but I still get the same issue.

These are some tests I conducted:

  • I reflashed the firmware

  • From, Reddit, I have measured the voltages on the CR touch end and from the main board (without the CR touch connected, these are the results:

  • |COLOUR|PIN|Voltages on the CR touch end (CR touch not connected|Voltages on the main board end without the CR touch connected|

COLOUR PIN Voltages on the CR touch end (CR touch not connected Voltages on the main board end without the CR touch connected
White GND 0V 0V
Black +5V 5.02V 5.02V
Yellow SIG 0.24V 0.24V
Red GND 0V 0V
Blue OUT 3.16V 3.16V
  • The firmware I have installed is Marlin 2.0.6, Jun 11 2021, Ender-3
  • Manually deploying the CR touch - flashes with a red light
  • Self testing - flashes a red light
  • Nothing happens when running:
    • M280 P0 S10
    • M280 P0 S90
  • When trying to run the Z-axis it works as expected