Tom,
The 8th circuit breaker down on the left row in the front electrical compartment is the Dash air conditioner. It is a 30 amp auto reset circuit breaker, It controls both dash blowers, condenser fan and the compressor. If the blower fans are old and noisy, the amp draw will exceed the 30 amp rating. The schematic is in coach electrical for 2000 Marquis in "Coach assist"
Fred