I just built my i2 I've had laying around and ordered some cheap electronics kit off amazon. I'm using a 12v 30 power supply off amazon as well. I configure marlin and after messing with the endstops finally I get the motors to move. next onto the thermistors.
Both the bed and the extruder are working and reading 25c at room temp as long as the 12v power supply is turned off. as soon as I turn it on the extruder goes to 0c and the bed remains at 25c. I tested the thermistor and im getting ~99-98k ohms at around 25c room temp. I also went into marlin and changed the temp pins for the extruder from t0 to t2 in the ramps_pin.h script. same result.
Do I have a bad ramps/Mega? or has anyone seen this problem before? am I missing somthing in the firmware that might fix this or should I buy a less cheap ramps and mega? Thanks
