Notifications
Clear all

First Layer Calibration "Bed Heating ..." forever  

  RSS
bumgarb42
(@bumgarb42)
Active Member
First Layer Calibration "Bed Heating ..." forever

Just finished building my first Prusa MK3S+ kit and everything has gone smoothly until reaching the "First Layer Calibration".  The LCD has been reading "Bed Heating" for 30 minutes.  The estimated print time keeps going up, but the bed temp has only gone down, currently at 26 degrees.  I'm not sure what I should do here.

Best Answer by Diem:

OK, be careful with this first step; don't burn yourself - feel above the bed, is it warm? Feel the bed, is it warm?

In other words, you are testing to see whether the bed is heating but the sensor is not working or the bed is not heating while the sensor is probably OK.

I'm guessing you have no heat so:

Look at the picture on:  https://help.prusa3d.com/en/article/einsy-rambo-electronics-wiring-mk3-mk3s-mk3s_2107

Find the Heatbed connectors.

Pull out and reinsert the connections.

Does the printer work now?

If not, set the printer heating and check the voltage across those two connectors with a multimeter.

No voltage?  Turn off at mains and then check all the fuses.

Voltage but no heating?  Either the bed heater or its wiring is broken.

IF you have heating but no sensor look for the Heatbed Thermistor plug and repeat the above process.

Cheerio,

Posted : 12/07/2021 9:53 pm
Diem
 Diem
(@diem)
Noble Member
RE: First Layer Calibration "Bed Heating ..." forever

OK, be careful with this first step; don't burn yourself - feel above the bed, is it warm? Feel the bed, is it warm?

In other words, you are testing to see whether the bed is heating but the sensor is not working or the bed is not heating while the sensor is probably OK.

I'm guessing you have no heat so:

Look at the picture on:  https://help.prusa3d.com/en/article/einsy-rambo-electronics-wiring-mk3-mk3s-mk3s_2107

Find the Heatbed connectors.

Pull out and reinsert the connections.

Does the printer work now?

If not, set the printer heating and check the voltage across those two connectors with a multimeter.

No voltage?  Turn off at mains and then check all the fuses.

Voltage but no heating?  Either the bed heater or its wiring is broken.

IF you have heating but no sensor look for the Heatbed Thermistor plug and repeat the above process.

Cheerio,

Posted : 12/07/2021 10:22 pm
bumgarb42 liked
bumgarb42
(@bumgarb42)
Active Member
Topic starter answered:
RE: First Layer Calibration "Bed Heating ..." forever

@diem

Thanks for the response.  The bed was definitely NOT hot.  I quickly touched it a couple of times when it read 26 degrees and then finally sat my palm flat on the bed.  However, it was hot previously in the initial self test; I could feel heat rising off it while hovering my hand over it.  I'll check over the things you suggested.  Thanks for the help!

Posted : 12/07/2021 11:33 pm
bumgarb42
(@bumgarb42)
Active Member
Topic starter answered:
RE: First Layer Calibration "Bed Heating ..." forever

@diem

Update: I disconnected and reconnected the hotbed and hotbed sensor and reconnected.  Everything worked fine after that.  Thanks again for the help!

Posted : 13/07/2021 2:16 am
Share: