Two problems related to defogger have been reported for the 2002 GMC Yukon. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2002 GMC Yukon based on all problems reported for the 2002 Yukon.
When the defroster was turned on, it caused the windshield to crack.
Front heater only operates at full temperature setting 82 degrees. Otherwise, the heater is blowing cold air, about the outside air temperature. The only way to regulate inside temperature is to set at 82 degrees, then turn system off until the cabin is cold, then turn heater back on, etc. This needs to be done every few minutes, causing constant driver distraction. Dealer is advising gm tech center is stating the system is operating as designed. Dt.