Chrysler Repair: 99 Plymouth Breeze:Water leaking into air intake system, air intake system, intake plenum

Question
My sister owns this vehicle and is having trouble with it going through the fan speed module/regulator located under the dash on the right side.  After a rain, the module will only allow the fan to run on high.  Slow and medium stop working.  When the module is removed, it shows signs of water damage even though the repairmen say it is not the heater core leaking.  Where could this moisture be coming from?  Thanks for your help!

Answer
Hi Dawn,
I would suspect that the rain water is leaking in thru the air intake. I would put the system on recirculate mode before turning off the engine which will close the intake somewhat. Also I would remove the cowl cover (the air intake grill just in front of the windshield, after removing the wiper arms) and once you have access to that air intake plenum clean out the leaves and debris at the passenger end of it where there is a drain hole that if open will allow the rain water/wash water to drain out.
Roland