RAMPS board - no power to heatbed
I'm setting up my first 3D Printer, a Prusa i3 MK2 clone.
When I try to heat the bed, nothing happens. Then Marlin throws this error after a while:
Bed Heating Failed
In Pronterface I see this in the console:
Error:Heating failed, system stopped! Heater_ID: bed
[ERROR] Error:Heating failed, system stopped! Heater_ID: bed
Error:Printer halted. kill() called!
[ERROR] Error:Printer halted. kill() called!
There is 0 voltage across D8 on the Ramps board, where it is connected. When I heat up the hotend, on the other hand, which is connected to D10, I see 12V across the board's D10 terminals.
The bed is MK42 type.
My axes, extruder hotend and fans are working OK.
I previously burned out the 5 V regulator on my Arduino Mega by misconnecting one of the end stops. I replaced the regulator on the board and the 5 V supply seems to be working OK again. However I wondered if I might have damaged the board in some other respect? Or is there a config setting in Marlin I should change?