1997 GMC Jimmy Owner's Manual - Page 146

011 cool but sunny days, use BI-LEVEL A/C to deliver ~varm to the floor and cooler air to the instrument air p"nel outlets. When the air conditioner is on. you may sometimes notice slight changes in y o u r 1:ehicle's engine speed and power, This is normal because the system is designed to cycle the compressor on and off t o keep the clesired temperature. Heating Air Conditioning The heater works best if yo11 keep p l r windows closed while using it. On cold days. use HEATER With the ten~perature knob turned clockwise. BLEND is L I S S ~ L in I~ cool weather when you have fos or ice on the winclshield o r side windows. I f ~ O L Iuse the optional engine coolant heater befhre starting y o ~ engine. your heatin2 system will produce ~r warmer air faster to heat the passenger compartment i n cold weather. See "Engine Coolant Heater" i n the Index. 3-3