Hotend fan not starting automatically

Hi, my hotend cooling fan is not switching on. I have read somewhere that it automatically starts when temp increases above 50 degrees but mine not even starts at 200 degrees. The fan is working when I give the command m106 i.e. What could be the possible issue of not starting automatically? Help needed

There are normally two extruder fans

1) the part cooling fan. This is the fan controlled by M106/M107 used to cool the part as it is being printed. This is on FAN_PIN (FAN0_PIN in newer marlin)
2) the hotend fan. This is set with E0_AUTO_FAN_PIN, eg #define E0_AUTO_FAN_PIN FAN1_PIN It cannot be set to FAN_PIN (or FAN0_PIN) This is not controllable with M106/M107
This turns on when hotend temperature exceeds the set temperature eg #define EXTRUDER_AUTO_FAN_TEMPERATURE 50

Edited 2 time(s). Last edit at 08/15/2023 02:04PM by Dust.