Three problems related to defogger have been reported for the 1996 GMC Jimmy. The most recently reported issues are listed below.
Consumer complained that the heater blows cold air, heater core clogged leaking, coolant leaking onto floor, and muddy coolant, a/c was leaking, a/c fan has power surge from high speed to low, a/c compressor was replaced.
Heater failed.
Consumer stated that the air conditioner (a/c) is not cooling, leakage at the compressor and evaporator, leaking water into the floor, and the a/c fan intermittently has power surge from high to low by itself, heater blews cold air from heater core.