why does the heat come on when i turn the car on
If the temp is lower inside the car then it is on the outside the heater will come on until the temp is at the "set temp" , if if always comes on there is something wrong with the clima controller unit.
Check the owners manual, Saab has a customized prefered setting feature. I forget how to change the setting (see owners manual) but the climate control unit always goes to the preset temp. & fan speed.
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