Practice question
A vehicle's heater produces cold air even after the engine reaches operating temperature. What is the most likely cause?
- A thermostat stuck open preventing the engine from reaching proper temperature
- A clogged heater core due to coolant contamination
- Low coolant level preventing flow to the heater circuit
- A faulty blend door actuator in the HVAC system
Answer: A — A thermostat stuck open preventing the engine from reaching proper temperature
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