Before I had version V1.01 and I did not remember these issues.
Now mount V 1.02 with 2 fan connections
I'm testing the firmware 1.17 beta 7 and I'm having the same problems.
Cartridge inspection HE 12V 40w measured 3.8oHm.
The cables are ok
Have many problems with HE v6 and temperature swing a lot.
Tested with thermocouple and thermistor
Always swing a lot
Pid tuning many times
With 1.1.7 the temperature was always constant
This and the result of the cube test with oscillating temperatures