Nozzle and Plate Heaters Will Not Come On

harryinhbg

Neither the hot head nor plate heaters will turn on, and head temperature
readout indicates 460-500 Deg C, although everything is actually cold.
Plate temp reads correctly, but the plate heat will not come on either. I
pulled the thermistor leads from the RAMPS board, and checked
resistance compared to a new thermistor, and the thermistor reads
correct compared to others at room temp.

This is a Folgertech
Kossel 2020 (rev a) with Ardino 2560 and RAMPS Shield.  Repetier Host
V1.6.1  I have also checked all of the power lead terminals for
tightness.

The machine itself moves normally. I alao the Emergency Stop, and rebooted everything, including my Laptop, with no success.

Has anyone had a similar problem?  Unless someone
has some troubleshooting things I can try, I suppose the next step is to
order a new RAMPS board?

MrBaz

You need to make sure the pin configuration is correct in the firmware.  You also need to ensure the correct thermistor type is selected in firmware.

Repetier

With these reading sfirmware will go into dry run, see log. So it is either returning wrong resistance due to a short, you have a wrong thermistor type slected or connected to the wrong pins. Somethink like that.