When the AC is on, thare is an intermitant clapping noise coming from above the glove box. So far it is not causing any other issues, I would just like to eliminate it. Any ideas?

 

Not that I have any answers but what year, model, etc?

 

It is a 2000 S40 with the 1.9L L4 PFI DOHC 16V engine, and factory AC.

 

The fan is right behind the glove box in the far right corner. Also, the cabin air filter is behind the glove box above where your left foot would be when sitting in the passenger seat. The other thing I remember is the resistor for the fan is mounted inside the air box just in front of the cabin filter.

Does this sound vary with the fan speed? Is it only with A/C and not when heat is coming out the vents? Does it matter if you have recirculate on or not? When you say clapping noise you mean like hand clapping (applause)? Or like 2 objects hitting each other like thunder clapping?

 

I had not checked with this much detail until today. The sound is like applause or even clacking. It only happens when the AC is on recirculate.

 

Does the sound vary with fan speed? If no then maybe it's the motor for the recirc door. If the motor for the recirc door was somehow unhooked then you would hear it running continuously as it tried to open the door?

I'd guess if the sound varied with the fan motor speed then maybe something stuck in the fan blades. Two WAGs.....