# PID Autotune not working properly

I'm running the autotune PID because I had to replace the hotend. The command that I launch is M303 E0 S200 C9. But from the temperature chart I see that he has only made two cycles, after which the autotune control seems to have gone mad and has remained stable on 213° C and is no longer doing autotune cycles. After a while I get Recv: PID Autotune failed! timeout.

I am using Marlin Firmware version 2.0.3 (GitHub) installed on a MKS Gen v1.4 (Arduino MEGA 2560) board. The MKS Gen board replaces the original one of a Geeetech Prusa i3 Pro B. Hotend is 12V.

Do you have any suggestions? Has anyone experienced something like this?

UPDATE:

I redo the PID Autotune and now I get a sawtooth:

• sawtooth is good, it is rather close, though... not close enough. maybe tune with ess than 9 cycles? 3 to 5? – Trish Mar 10 '20 at 17:09
• I am giving a try using 3 cycles. – kitsune Mar 10 '20 at 17:25