f/w Marlin TH3DUF 1.8.5
I have a modded cr10s and have switched the 2 Z stepper motors to the front . BLTouch seems to have a hard time homing Z axis. It boots up fine and does a self test.
Using G28 or Autohome on the controller should send it down to the center home position, but instead goes up.
I've switched the stepper cable pins around so should send it in the correct direction downwards, but it still goes upwards.
X and Y do home correctly but the red light on the BLTouch does not illuminate like it should with the pin extended.
Would it be better to switch the cables around on the board and returning the cables to their original position on the motors?? If i remember the z axis upgrade included a new cable what i used which was split at the printer end to plug into each motor and a single connector at the other end fitted to the board.
Maybe thats the issue.
You should use M119 gcode to verify the BLTouch first. If the BLTouch is "triggered" without hitting the probe, you might want to toggle the following setting. The Z-axis will go up if the z-endstop is "triggered" without really triggering it.