Yesterday I had a problem with the wire coming off my heatbead - I re-soldered the wire back on and re-attached my bed to the printer. I didn't print anything but the bed was heating when tested in Repetier and the various axis were moving.

Today however Repetier / Pronterface etc are falling over on the basis that the 'extruder is switched off'. It looks like an extruder test is the first check that the software does when connected and if it doesn't pass the test it falls over and won't allow access to any other functions.

I've checked the power cables to the extruder and they appear to be connected fine at the board and everything seems to be sitting fine in to the extruder itself. The thermistors seem to be attached OK to the board as well.

I've re-seated the stepper to make sure it's seated correctly. The green lights on the RAMPS are on. I have the extruder fan wired to run constantly and that is running so power is getting through the board.

Any ideas appreciated - this printer has been nothing but trouble for me.

For reference. I've managed to solve it...

I connected only by USB (without the PSU on) and double checked the settings in Repetier. The connection port had reset to Auto, I changed it back to COM5 and it's now heating when I try it.

I had tried COM5 earlier but with the PSU powered on and it didn't work so why just using the USB allowed me to connect and overcome the error I don't know.