- the thermostat does not close, as a result of which the liquid is not heated sufficiently and does not heat the heater radiator well - replace the thermostat (see subsection 4.3);
- the heater hose is clogged, preventing the flow of fluid through the radiator - disconnect the hoses and flush the radiator with a stream of water from a hose;
- if water does not pass through the heater radiator, then the radiator is clogged and must be replaced.
2. If air does not come out of the air duct outlets, proceed as follows:
- turn the ignition key to the ON position and turn on the fan (the noise of the running electric motor should be audible);
- if the hum of the electric motor is not heard, or if the test shows that the switch and resistor block are working properly, then the cause may be a faulty electric motor.
3. If the mat is damp or coolant vapors are leaking through the vents, the heater core is leaking. Replace the core.
4. Check the moisture separator drain hose for cleanliness.
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