Two problems related to defogger have been reported for the 1998 Buick Lesabre. The most recently reported issues are listed below.
On September 21, 2000 I had my Buick Lesabre to the dealer because the rear window defroster did not work. They replaced the module. The defroster than worked. On December 8, 2000, I was on my way home from work. I had my rear window defroster on, but it had shut off. I noticed an awful smell. As I was stopped at a stop light, I looked around for the source of the smell. As I glanced over my shoulder, flames were beginning to come through the panel between the rear window and the side window. I had the car towed to the dealer and they determined that it was the rear window module that had caused the fire. The car is being fixed and checked over by another service company. They are checking out the wiring to see if the defect might be some where else.
When heater is on strong odor is present, causing irritation.