Table of contents: No hot air enters the car interior ↓ No cool air enters the car interior ↓
No hot air enters the car interior
Thermostat is faulty. Replace.
The heater control drive is faulty. Check and make any necessary repairs.
The heating hose is clogged. Eliminate the cause of the blockage or replace the hose.
The heater heat exchanger's patency is impaired. Clean or replace the heat exchanger.
[Data copied from web resource: www.nissanbook.ru]
Note: Make sure the engine is at normal operating temperature. If unsure, check the thermostat for proper operation.
After the engine has warmed up, both heater hoses should be warm/hot to the touch (see accompanying illustration). If the heat exchanger is not passable, one hose will be noticeably colder than the other.
No cool air enters the car interior
The air conditioning compressor drive belt is slipping or broken. Replace the belt and/or adjust its tension (see the relevant subsection in Chapter Settings and ongoing maintenance).
The coolant level has dropped. Check the system for leaks (see accompanying illustration), add if necessary.
The air conditioning compressor is not functioning properly. With the ignition on, turn on the air conditioning system and make sure that the compressor clutch is engaged; a distinct click should be heard. Otherwise, before proceeding to remove the compressor for repairs in a specialized workshop, check the correctness of the power supply to it.
The warm air from the heating system is mixed with the cooled air. Check the heating system for proper operation. Adjust the control cables. Replace defective components.
Note: The diagnostic procedures listed above are only basic checks. If there is a strong suspicion that the air conditioning system is not functioning properly, it is recommended to take the car to a specialized workshop for a series of professional checks and necessary repairs.
Don't be alarmed if you find traces of water under your car when it's parked in hot weather. Usually, it's just condensation that forms during the operation of the air conditioning system.