Automobile Air Conditioning Clutch - Brake System

For vehicles with pneumatic braking systems, the preload force of the balance spring inside the brake master cylinder should be adjusted properly. Excessive preload will result in a stiff brake feel, causing sudden braking upon pedal depression. Such braking performance poses a high accident risk on icy and slippery roads in winter.

For vehicles with hydraulic braking systems, additional attention should be paid to checking the brake fluid, brake pipelines, and all wheel cylinders for leaks. If any leakage is detected, the brake fluid must be replaced promptly.

The parking brake also requires adjustment. Its braking effect is applied to the drive shaft through mechanical transmission. During braking, the braking force is evenly distributed to the two rear wheels via the two half-shafts, which can effectively prevent braking deviation between the two rear wheels. In other words, using the parking brake on icy and snowy roads can prevent tail skidding, thereby reducing the probability of accidents.

For the inspection of the parking brake, the number of clicking sounds emitted by the locking mechanism when pulling up the handbrake should not exceed three. If the number reaches five, it indicates that the parking brake clearance is too large, and adjustment must be carried out immediately to reduce the free travel, thus ensuring driving safety effectively.

In winter, the automobile air conditioning refrigeration system is left unused for a long time, which may lead to seizure of moving parts. This will increase the starting resistance torque, causing slipping and excessive wear of the AC electromagnetic clutch. In addition, it may also lead to dryness and adhesion of shaft seals, resulting in seal failure and refrigerant leakage.

Therefore, the key point of winter maintenance for the automobile air conditioning refrigeration system is to start the system 2–3 times a month for about 10 minutes each time. This consumes little fuel but avoids major damage to the evaporator and compressor. It is advisable to start the refrigeration system on sunny days when the temperature is above 10℃, and run it for 10 minutes during driving.

The warm air system is also prone to malfunctions if left unused for an extended period. First, check whether hot air is blowing normally, whether the blower operates without abnormal noise, and whether the air ducts are unobstructed. Sometimes, the problem arises when the antifreeze in the heater hoses stops flowing for a long time and solidifies, blocking the circulation pipelines. Although this does not affect driving, the maintenance work is rather troublesome.