Question

a customer complains that the heater works sometimes, but sometimes only cold air comes out while driving. technician a says that the water pump is defective. technician b says that the cooling system could be low on coolant. who is right?
technician a only
technician b only
both technicians a and b
neither technician a nor b
question 6
1 pts
the normal operating temperature (coolant temperature) of an engine equipped with a 195°f thermostat is ______.
175°f to 215°f
185°f to 205°f
195°f to 215°f
175°f to 195°f

Explanation:

First Question (Heater Issue)

• A defective water pump (Technician A) can cause inconsistent coolant flow, leading to the heater sometimes working and sometimes not (as coolant carries heat for the heater).
• Low coolant (Technician B) means there's not enough heated coolant to consistently supply the heater, also causing intermittent cold air. So both A and B’s diagnoses are valid.

A 195°F thermostat starts opening around 195°F, and normal operating temperature for such an engine is typically a range around the thermostat’s set point, extending a bit higher (due to system dynamics) but not too far. The range 195°F to 215°F aligns with this, as the thermostat allows coolant flow to regulate temperature, and normal operation stays near or slightly above the thermostat’s set temp while accounting for engine load/conditions.

Answer:

Both technicians A and B

Second Question (Engine Operating Temperature)