Selfttest error: Please check/ Not connected - Heater/Thermistor  

Selfttest error: Please check/ Not connected - Heater/Thermistor

Hi there, 

I've assembled my new MK3S+ kit and can't get past the 'Heter/Thermistor' error during the selftest. It keeps failing while attempting to warm up the heat bed. 

What did I try so far? 

• Used a hair dryer on the bed and extruder while the printer was on -> The LCD screen displays a rise in temperature for both.
  • I assume this means that both thermistors work correctly. Could anyone confirm? There isn't anything else that would react to temp changes except for thermistors(and display it on the LCD screen :thinking:) ?? 

I followed this guide https://help.prusa3d.com/article/multimeter-usage_2117 .

• the Einsy heat bed power shows zero voltage (measured against the screws on Einsy board, the two most to the right),
• the 2 PSU power connections display 23-24ish voltage. 

So, being a complete electronics noob, it looks like there is no voltage to the heat bead at all. I'm stuck now as how to proceed and troubleshoot. Do I need a new Einsy board, change the screws, fiddle with the cables? Does anyone have tips for me?