Heating & A/C (A7)Question 89 of 120
Technician A says a stuck-closed blend-air door can cause no heat even with a good heater core. Technician B says a failed blower motor can cause no airflow from the vents. Who is correct?
a.Technician A only
b.Technician B only
c.Both A and B
d.Neither A nor B
Explanation
A blend door controls how much air passes over the heater core, so a stuck door can cause no heat, and a failed blower stops airflow entirely. Both technicians are correct. Actuator and door faults are common causes of temperature-control complaints.
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