Fan stopped working - is a mystery why

We drive a 1999 Nissan Quest Mini Van. Earlier this summer, our fan, which has 4 levels, stopped working on levels 1 & 2. The good news is that the fan worked on the two higher levels: #3 & 4. A few weeks after fan levels 1 & 2 stopped working, # 3 then stopped working. We have survived the summer months with the fan/air blowing on high, on #4. We have to yell at each other over the swooshing of the fan on high level, but we get cool air. Now - here is my dilema: Previously we owned a 1994 Nissan Quest Mini Van, and the same thing happened, only all four speeds stopped working. We had no fan at all - except at high speeds when the air would blow through the vents all on its own. We took the '94 Nissan to the Nissan dealer. They could not find the source of the problem. They took apart the entire dashboard, etc. and after about 5 hours and $800.00 they asked if they should stop looking - Ouch! I still had to pay the bill and the fan still did not work! We survived 3 summers without airconditioning or the air blowing (the clip on fans were great) but the winters! brrrr. I nearly froze my feet one wintry afternoon driving down from upstate on NY State Thru’way, 87 in bumper to bumper with no heat. I am terrified that we’ll lose power on the fan in our current car with the same thing happening, and certainly cannot afford to pay $800 for the repair of the fan with no results - again! What am I to do?! A new car is out of the question…with two kids in college…help! Thank you so much.

Mitch and Cathy

PS - love your show!!!

The fan speed control uses a resistor pack that is located in the ductwork near the fan motor under the passenger side dash. There should be an 6-wire electrical connector on a module that can be removed from the ductwork. The resistor pack will cut voltage to the fan to control the speed. Speeds 1, 2, and 3 use progressive resistors to the motor. Speed 4 by-passes the resistors and sends 12V to the motor. I would start there. Most modules like this can be had at the dealer for $40-80. Some may be more.

Hi - belatedly, just wanted to thank you for your reply. We were able to take your info to the garage & got the fan fixed just as you advised and for $80. So thanks!
Mitch & Cathy