9-5 Aero (9600) L4-2.3L Turbo (B235) HO (2000)
27.
Remove the stepping motor.
28.
Remove the air duct from the heating and ventilation unit.
29.
Check whether and where the air mixing damper shaft is ruptured (by using a mirror). Wipe away any grease to see properly.
30.
If the shaft is not broken then check the function of the stepping motor (detached motor) using Tech2 (the "Activate" menu).
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If the shaft and stepping motor are in working order then check whether the heat can be controlled manually by rotating the shaft manually