Z axis won't move down, only up, after BL Touch install

Ender Series Creality Ender-3 V2
1

Hi,
I recently installed BL touch on my ender 3 pro. Now I am having problems with my Z axis. I have tried Factory reset the firmware. If I manually reset the printer, z axis works just fine, but once I autohome, the z axis down just stops working – it goes up, but not down.
It can’t be a hardware issue, as the z axis works fine if I cycle power. It can’t be firmware, because I ran M500 factory reset. I’d appreciate any suggestions.

2

Hi Alexander. Ther are two possibilities for the Z drive not going Down.

  1. An open circuit in the Z limit switch - The black and white wires from the BLTouch.
  2. Depending how the Marlin firmware has been configured. The black and white wired my need to be in the old Z limit socket on the control board or in the 5 pin socket marked BLtouch. pins G and out.

Bill