common defective error
- temperature sensor read wrong
hot air handle
yellow wires 220VAC
3V and 5V DC also on board for fan-dat, etc
wires
✅ In a hot-air handle with only heater + temperature sensor, no fan and no reed switch
The internal parts are:
Heating element (ceramic heater) → always 2 wires
Temperature sensor → usually 2 wires
Protective ground wire → 1 wire
This adds up to 5 wires, matching your description.