Geeetech A20M hot end problems??

Hi all,my A20M used to be working fine. However, I now can't get anything to print. Filament is extruded, but it soon clogs. I have tried new filament, a new extruder, new nozzle and finally a new hot end. The problem remains.I just pulled the filament out from a cold hot end and found the following in the attachment. Does this look like a heat creep problem?The A20M does not have a hot end fan, so I bought one in the hope of helping with the heat creep. The problem now is where do I plug it in? The attachment shows the circuit board for the hot end. The connector circled in green is where the hot end temperature sensor is plugged in. The one circled in red is where the filament cooling fan is plugged in. The plug on the fan I bought is the same conenctor as with the temperature sensor. The filament cooling fan plug is smaller.Where should I plug the new fan in? Will this automatically be recognised ba Marlin?Thanks in advance for any help.RegardsRichard