HVAC Blower Motor Replacement

[RNajarian]

I’m embarrassed to say I’ve suffered with this problem for nearly 8 years, despite a straightforward fix thanks to Pelican Parts. The problem: Inoperative/Ineffective A/C on my 2005 V6 Cayenne.

The moral of the story is listen to the experts.

The symptoms were initially everything works normally in the A/C system, but ultimately the blower motor quits. Airflow in the rear vents seem to be normal but all front vents quit blowing air. I eventually figured out a complete shutdown of the A/C system and restart 20 seconds later would allow the blower motor to work again for a period of time. If I put the fan setting on high it would work for a longer time. The symptoms seemed to be worse in HOT (100 degrees F) weather.

Armed with Wayne’s Tech article on this subject I diagnosed the problem.

https://www.pelicanparts.com/techarticles/Porsche-Cayenne/35-ELEC-HVAC_Blower_Fan_and_Regulator_Replacement/35-ELEC-HVAC_Blower_Fan_and_Regulator_Replacement.htm

This is where I made a needless error. I did not heed his suggestion to replace BOTH the regulator AND the blower motor. I was intimidated by removing 1/2 the dash.

In 2015, maybe 3 years after I first noticed the problem I decided to address the problem. I replaced only the regulator. The problem didn’t completely go away, but the system worked well enough that only occasional resets were warranted. The truck isn’t my daily driver. I put less than 5000 miles a year on it in mild weather (mid 80 degree temps.) so the problem was manageable.

In 2019 the problem got worse, so I thought my eBay regulator purchase was the problem. This time I bought a new regulator and blower motor from our host, but chickened out again and only replaced the regulator. The system worked OK. It still failed but due to the light use of the truck I let it go.

Fast forward to July 2021. My wife decides to escape the 90 degree LA temperatures by going to the outlet malls in the 120 degree Palm Desert heat. As you can guess the system failed quite often. It was so bad the system would only work with the fan on full. Nevertheless it still failed. At this point I pledged to bite the bullet and “finish the job.”

We got back home Sunday at 5:00 pm. Armed with Wayne’s article I began to replace the blower motor. Surprisingly it didn’t take long at all, maybe 2 hours. At 7:00 pm, testing the system in the driveway everything seemed to work. The real test would be our next outlet mall expedition. The removed blower motor fan looked OK. No obvious failures, except I did notice the electrical blade connections were black, not the expected copper color.

Recently we took a 4 hour trip, 90 miles in bumper to bumper traffic. Much to my delight the system performed as designed. I forgot all about how well the automatic climate control feature of the truck worked. The fan speeds were mostly on low during the trip and the system suffered no problems. A recent R134 top off had vent temps in the low 40s.

Hopefully everything keeps working the way it is now.

Thanks PP for your help.