Auto AC Compressors
Civic AC compressor
Reflect the air-conditioning system is not cooling. The inspection found no voltage Civic AC compressor electromagnetic coil, the compressor does not work for the two cooling electronic fan not working. The AC compressor control whether to work performed by its electromagnetic clutch, with the development of technology, the modern car Civic AC compressor operating modes continuity and intermittent work can be divided into two kinds. The former is a variable displacement compressor, such as Shanghai GM Buick, Volkswagen Audi are using this, as long as the open air ( air conditioning mentioned here are generally refers to the refrigeration system ) , the compressor has been working, rely on compression the pressure inside the valve to control refrigerant flow to wither control cold effect. Latter in the air conditioning is turned on, mainly based on the temperature of the evaporator to control the compressor off, often used this model Japanese cars , such as Toyota, Honda. While comfort is not as good as the former, but its fuel economy is better. The authors have several years of experience in the maintenance, a brief overview of the working conditions of the AC compressor, not the comprehensive, also please counterparts’ correction.
1 . The engine speed is too low, in order to ensure the operation of the engine, the AC compressor is usually disconnected. Engine at full load, in order to take into account the dynamic performance of the engine, the Civic AC compressor does not work, for example, in emergency refueling compressor instantaneous disconnect can be manifested.
2 . The runtime engine failure. The engine control module detects abnormal to an important part of the engine into limp state, the air conditioning also will not work. It is just like a person is sick, can not let him live dry heavy.
3 . When the engine water temperature is too high or the water temperature sensor failure, in order to protect the engine, the air conditioning was also cut off, but this condition is relatively easy to be overlooked.
4 . Some automotive Civic AC compressor assembly speed sensor, the conveying speed signal when the air conditioning is turned on, the sensor to the control module. When the compressor or sensor failure, the solenoid is cut off, this can effectively prevent further expansion of the scope of failure. Toyota Crown like the old models, the occurrence of such failure, the compressor is working for a few seconds after being shut down, the air conditioning panel on the A/C lights start flashing to warn. There is engine belt serious skid, engine speed and AC compressor speed difference is too large, the same will make power protection.
5 .The air conditioning system will not start when the ambient temperature is too low or abnormal.
6 .When the evaporator temperature is too low, the compressor is turned off, in order to prevent its freezing.
7. When the system pressure is too high or too low, in order to protect the air-conditioning system, the compressor is cut off. I repaired a Honda Accord, air conditioning, intermittent refrigeration and cooling effect is not very good, and the cause of the malfunction, leading to bad cooling electronic fan air pressure is abnormally high, the compressor stops running when the pressure is slowly reduced air conditioning work, and so forth.
8. Air conditioning request signal. Broadly divided into three forms: the first one is relatively simple mechanical manual air conditioning turned empty withered request sent to the engine control module signal processed by the engine control module, control compressor relay. Another is the air conditioning panel after receipt of the air conditioning turned instruction performs arithmetic processing by the air-conditioning panels meet the conditions, controls the compressor relay, while the air conditioner turned on the signal tells the engine control module. Another exchange of information between the air conditioning control panel and the engine control module, and then make the appropriate instruction.
9. The feedback signal of the blower of the air conditioner. Due to other faults cause the air conditioning blower no wind, compressor, it will not work. For example: Guangzhou Honda Accord cars, blower transistor damage, open empty withered there is no reaction, generally is transistor inside a thermal fuse breaker.
Accord AC Compressor
Air-conditioning compressor as a high-speed rotation of the working parts, the probability of failure is high. Common problems include abnormal sound, leakage, and other malfunctions.
(1) Abnormal sound caused by many reasons for the abnormal sound of the compressor. Example, compressor electromagnetic clutch damage or serious internal wear of the compressor can produce abnormal sound.
1. Compressor electromagnetic clutch is 3 common site of the abnormal sound. The compressor is often damage from low speed to high speed operation, so the requirements of the electromagnetic clutch is high, and the installation location of the electromagnetic clutch is generally closer to the ground, often come into contact with rain and mud, when the electromagnetic clutch bearings under high load time will produce abnormal sound.
2. In addition to the electromagnetic clutch, the compressor drive belt tightness is also a direct impact on the life of the electromagnetic clutch. The transmission belt is too loose, the electromagnetic clutch is easy to slip; drive tape tight, the load will increase on the electromagnetic clutch. Transmission belt tightness is not the time, and at worst will cause the compressor does not work, the weight will cause damage to the compressor. When the transmission belt work, if the compressor pulley third generator pulley is not in the same plane, it will reduce the life of the drive tape or compressor.
3. Electromagnetic clutch pull will cause the compressor to appear abnormal sound. Power generator, air- conditioning system pressure is too high, or the engine load is too large, these will result in the repeated pull of the electromagnetic clutch.
4. Electromagnetic clutch with the compressor mounting surface should have a certain gap, if the gap is too large, then the impact will increase, if the gap is too small, will be with the compressor mounting surface movement interference between the electromagnetic clutch This is also to produce a common cause of abnormal sound.
5. The compressor work required for reliable lubrication. Lack of lubrication of the compressor or the use of lubricants inside the compressor will have a serious abnormal sound, and even compressor wear scrapped.
(2) Leakage of refrigerant leakage is the most common air conditioning system. Compressor leakage parts are usually in the compressor 3rd the high and low pressure tube junction, here is usually because the reason of the installation location, check up is too much trouble. The high internal pressure of the air conditioning system, when refrigerant leaks, compressor lubricants will be followed by the loss, which can cause poor lubrication of air-conditioning system does not work or compressor. Air conditioning compressor has a pressure relief protection valve, pressure relief protection valve is usually a one-time use, the system pressure is too high pressure relief, pressure relief protection valve should be replaced.
(3) Air conditioning compressor does not work for many reasons, usually because of the associated circuits. Preliminary check by way of direct transmission of power to the compressor electromagnetic clutch compressor is damaged.