Stops heating after you start to print

[kb3lnn]

I have a prusa I3 pro C and it just started to stop heating after you start a print. I check the volts and it is fine before and and after I start to print. I have changed the heating element and sensor. I am thinking may be the firmware is causing this.Could this be true? Or maybe the power supply. I really would appreciate and help.

Robert KB3LNN

[William]

Hi,You can check if your wiring is fully connected.
Then check to see if the thermistor at the hot end is fully connected.
If fully connected, try measuring the thermistor at the hot end.

[kb3lnn]

And adding to my post found that can not get heat block to heat again till I disconnect and re-connect. This is really annoying.

Robert KB3LNN

[kb3lnn]

Also I can leave the heat on for a long time with no change and temp is very stable. But as soon as I start a print it drops in temp and cannot get it to come back up till I disconnect and re-connect.

[kb3lnn]

Yea I have changed both the sensor and heating element.

Robert KB3LNN

[William]

You can check if you are fully connected,
and poor contact can also cause this to happen.

[kb3lnn]

I even went as far as replacing the mother board. Lucky I had a spare on the bench. I am leaning towards the main power supply.

Robert KB3LNN

[William]

You can check if your power box voltage is adjusting the voltage range required in your country and can measure the output voltage.

[kb3lnn]

Everything was fine for 4.5 years no problems at all. I print about two 2.5 Lbs. of filament a month. I will replace the main wires that go to the heating element an see if this helps.Also while I had the printer on the bench I removed the cover on the power supply and it was full of dust, not surprised after 4.5 years, cleaned it out. Thanks all for your help.

Robert KB3LNN

[kb3lnn]

Thanks to all for your replies. I found the problem a wire to the heating element was frayed and not making a soiled connection. But this was not on the ends as you would think, it was in the middle, go figure. Anyway Thanks again.

Robert KB3LNN