Unstable hotend temperature

[DaliborBalic]

Hello guys,
i changed hotend on my A30 and having troubles with temperure. When i set 200° it will go to 260, then it will just bounce from 190 to 215 all over again and again.
I did some research hear and there, i tried to change PID parameters in smatto, but whatever numbers i put, it will always make the same.
The only thing that might change is that if i put higher P value, after few minuts o printing the temperature will just drop down do 0.
I've tried two different hotends, and with both is the same.
Does anyone know how to fix this?
I am using all latest drivers.

[William]

Hi,
I think you can try to click the "default factory".
Then test it again.
Could you attach the values of yours(The PID).
eg:M303 E0 S200 C5

[DaliborBalic]

Hello Wiliam,
i tried restoring to default, no difference,
i tried any kind of PID parameters, no difference

Edit... actually now it goes very high only at beggining, then it oscilates for only +-1° which is cool i think.

I did restore default before and it did nothing, not it seam pretty much OK.
Thank you very much

[DaliborBalic]

i was too quick on giving answer to Wiliam, and too quick to edit it.
after running a few hours print this is result.
First the temperature went very high, but soon stabilize to normal print temperature, but after about one hour, it started oscilating again, and at some point temperature just droped down to death.
From starting the print, there was no manual changing of any parameter, i clicked run, and never touched the printer.

[William]

Hi,DaliborBalic

You can try to update your fw to V1.38.59 at first.
Then set the PID for it again.If you have set the PID but it the issue still on.
You need to check the PSU+ mosfet at first.
If the PSU has an issue then the printer won't work normally.
Or you can try to check the mosfet of the E0 with the multimeter.