Hello all,

Hope this will fit in this forum.
I've had issues with my new BLtouch not performing the self test upon power up.Instead it steadily blinks red but it still will function fine as far as bed leveling goes.
Hunting through the forums, I did not find a lot of info, other then check the wiring and it is defective...

Then I found info at Antclabs that proved helpful..
Quote..
2) if the red LED in BLTOUCH flashes at 80% duty right after the 3D printer is switched on, please release it with S60 or S160.

It's a message to check Wiring because your 3D printer board is already sending a control signal to BLTouch before BLTouch power is turned on. Don't worry, your 3D printer and BLTouch work perfectly even if the Red LED flashes at 80% duty.
Unquote..

This was exactly the scenario I was having.I suspected that the command signal pin may be"floating" during boot of my Rumb+ board.
Installing a pull-down resistor from the command pin to ground solved the issue for me (4K3 Ohms).

Perhaps this info will help others..

Bart

I joined this forum just so I could thank you for that post. I was looking everywhere for that answer. Cheers!