Blocked fan. (reference 1 image "Lamp rear fan connections")

Unblock the fan. Ensure the fan can turn freely.

Damaged wire unit of the fan. (reference 2 & 3 image "Lamp rear fan connections")

Check if the wire unit of the fan is not damaged. Repair if possible, otherwise replace with new one.

Fan end of life.

Replace the fan.

Malfunction Fan Control board.

Replace the Fan Control board. See "Lamp Info Module fan".

Fan end of life.

Replace the fan. See "SMPS compartment fans".