Home › CDL Practice Tests › General Knowledge Questions › Question 368
What is the engine fan's role, and when might the driver use a manual fan control if equipped?
- A.The fan cools the cab only
- B.Manual fan use is never helpful
- C.The fan pulls air through the radiator; engaging it early on a long hot climb, if the vehicle allows manual control, helps hold coolant temperature down
- D.The fan charges the battery
Correct answer
C. The fan pulls air through the radiator; engaging it early on a long hot climb, if the vehicle allows manual control, helps hold coolant temperature down
Why
At low road speed on a grade, natural airflow is weak exactly when the engine works hardest, so the fan does most of the cooling. Bringing it on before the temperature climbs is preventive; waiting until the gauge is in the red is reactive.
Manual topic: Engine Controls - Fan · From the General Knowledge practice bank (GK-368).