FIXED: I couldn't find a fix for this on Marlin 1.x, but updating to to Marlin 2.0 got rid of the issue.by nichlock - Firmware - Marlin
I am having an issue related to a newly purchased (genuine) BLTouch v3.0 and my i3 based printer running Marlin-1.1.9 on a RAMPS1.4 board. Around 15-20 seconds after the z-axis is homed using the BLTouch sensor, a ‘heating failed’ error is thrown, even without any heaters active. The BLTouch itself works as expected when homing and when using M280 commands. Error always occurs 15-20 seconds afterby nichlock - Firmware - Marlin