I have a 2003 Infiniti G35.

Issue: My mechanic said my AC Condenser Fan was stuck on High. My Mechanic said that the IPDM is the cause of the AC Condenser Fan being stuck on high. I took it to Infiniti for a second opinion. Infiniti Dealer said due to the AC Condenser Fan being stuck on High, I needed to replace the AC Condenser Fan and Motor Assembly.

I replaced the AC Condenser Fan Motor per Infiniti's suggestion (part 92120-AM700). Infiniti installed the part. However, my mechanic is stating that the AC Condenser Fan is still not working properly because the IPDM that powers the AC Condenser Fan is not working.

Questions:
1) How can I tell if the newly installed AC Condenser Fan Motor is running at both Low and High Speed? I don't want to take it back to Infiniti unless I can ensure the AC Condenser Fan is not working properly as my mechanic is suggesting.
2) What is the proper function of the AC Condenser Fan? Should the AC Condenser Fan turn on immediately as soon as the AC is turned on?
3) Does the AC Condenser Fan have two speeds (high and low)? The reason I ask is because one Infiniti shop stated that the AC Condenser Fan only has 1 speed.

I'm confused and I don't know who or what to believe.