Air conditioning system
Attention! The air conditioning system is constantly under high pressure. Never disconnect refrigeration lines or remove any system components without first discharging the system. The discharge of the air conditioning system must be carried out by an experienced specialist in a car service workshop.
A/C maintenance procedures are described in the relevant Section of the Chapter Vehicle settings and routine maintenance.
Heating system
1. If the heater does not provide proper heating of the air supplied to the passenger compartment, the reason for such a failure may be one of the following:
- The thermostat is stuck open, preventing the engine coolant supply to the heater heat exchanger from reaching normal temperature. Replace thermostat (see Section Check of serviceability of functioning and replacement of the thermostat);
- There is a violation of the patency of the cooling tract, which blocks the supply of coolant to the heater heat exchanger. Feel the hoses connected to the nozzles on the rear bulkhead of the engine compartment - both of them should be hot, otherwise the patency of the tract is broken (blocked hoses, heat exchanger, or heater control damper). Disconnect the hoses and back-flush the heat exchanger. Flush both hoses as well;
- If it is not possible to restore the patency of the heat exchanger by flushing, it should be replaced (see Section Removal and installation of the block and heat exchanger of a heater).
2. If the heater fan speed does not match the selected position of the corresponding switch on the system control panel, check the condition of the fuse, connecting wiring, relay, switch and resistive assembly.
3. If there is no air outlet through the deflectors at all, take the following actions:
- Switch on the ignition and activate the heater fan. Press your ear against the deflector and try to hear by ear if the drive motor is working;
- If there are no sounds confirming the correct functioning of the motor, and the resistive assembly is in order, the motor should be replaced (see Section Checking the functioning of the heater fan drive electric motor and replacing it).
4. Moistening of the carpet on the floor under the heater heat exchanger, or steam escaping through the air duct deflectors indicate heat exchanger leaks. Remove heat exchanger (see Section Removal and installation of the block and heat exchanger of a heater) and replace it with a new one (the heater heat exchanger cannot be repaired).
5. Check the patency of the drain hose coming from the heater/evaporator assembly and routed to the right side of the bulkhead. A blockage in this hose can cause steam to escape from the duct deflectors when the heater is turned on.
Eliminate air conditioning odors
1. Unpleasant odors that often occur when A/C is turned on are caused by the formation of mold colonies on the evaporator heat exchanger plates.
2. Specialty aerosol disinfectants designed for servicing air conditioning systems are available from almost any automotive accessory store. It should be remembered that the price of a tool is usually directly proportional to its effectiveness. Switch the system to closed air circulation mode and turn on the heater fan at maximum speed for ten minutes. In order to dry the system, turn on the heating to maximum intensity. Disconnect the electrical wiring from the compressor to prevent it from tripping.
3. The supply of the agent is usually carried out through a long hose. Remove the heater fan motor resistor assembly (see Section Checking the functioning of the heater fan drive electric motor and replacing it), insert the nozzle of the supply nozzle into the resulting hole and move it to the left, pointing at the evaporator heat exchanger. The supply of the product is carried out in accordance with the instructions of its manufacturer. Try to treat the entire surface of the heat exchanger as completely as possible. The duration of each processing cycle and the intervals between series must be indicated on the container label.
4. The best preventive measure against mold colonization in the evaporator heat exchanger is to regularly check the patency of the drain pipe, and briefly turn on the condensate removal mode after each long trip with the air conditioner running to dry the evaporator.