What is the difference between A and M in car air conditioning?

1 Answers
DiEloise
07/29/25 12:53am
Here are the differences between A and M in car air conditioning: 1. Different functions: The A in car air conditioning represents automatic control of the car's internal and external circulation, while M represents external circulation. When the A button is pressed, the air conditioning system will automatically determine whether internal or external circulation is needed based on the air quality outside the car; when the M button is pressed, the car is in internal circulation when the light is on, and in external circulation when the light is off. 2. Different purposes: The internal and external circulation in a car serve different purposes. External circulation mainly provides ventilation. When the air inside the car is polluted, the car needs to turn on external circulation to replace the air inside; when internal circulation is turned on, the air inside the car does not flow, and the air circulates in a closed environment.
Was this review help?
10
4
Share
More Forum Discussions

What is the fuel consumption of the Mengshi?

Dongfeng Mengshi has an average fuel consumption of 11.3L per 100 kilometers. The specific fuel consumption standard should be based on actual usage, as fuel consumption is related to various factors, such as load, uphill driving, air conditioning usage, low tire pressure, etc. This model is equipped with a 6.5t engine, which results in relatively high fuel consumption. The main factors affecting fuel consumption are as follows: Engine: This is an inherent factor affecting fuel consumption. From a purely technical perspective, direct fuel injection is an excellent technology. Transmission: Here, transmission refers to automatic transmission. The engine and transmission form the simplest power output system, so the construction of the transmission also directly affects fuel consumption. Driving habits: This is an acquired factor affecting fuel consumption and also the most significant factor influencing fuel consumption.
9
1
Share

What is the weight of new energy electric vehicles?

New energy electric vehicles typically weigh around two tons. Below is an introduction to vehicle weight and its impact on fuel consumption: Weight of other vehicle types: Micro cars weigh approximately 700 kilograms, sedans weigh over 900 kilograms, generally around 1.2 tons, while jeeps usually range between 1 to 2.5 tons. Impact of weight on fuel consumption: The curb weight of a vehicle refers to its own weight, which includes the weight of the car under normal driving conditions plus any attached accessories. The curb weight is also an important parameter affecting a car's fuel consumption, as there is a proportional relationship between fuel consumption and curb weight—meaning that vehicles with greater curb weights consume more fuel.
5
2
Share

How Many Liters of Transmission Fluid Does the Highlander Need?

When replacing the transmission fluid in the Highlander, manual fluid replacement (gravity drain) requires 4 to 6 liters; using a fluid exchange machine requires approximately 9 to 12 liters. Functions of transmission fluid: Reduce friction and wear, control clutch friction and synchronizer performance; bear loads (low-speed high torque, vibration loads), dissipate heat, reduce vibration and noise, remove contaminants from gear meshing (cleaning function); prevent corrosion, pitting, and surface metal tearing, isolate metal surfaces, and prevent direct metal-to-metal contact. Hazards of not replacing transmission fluid for a long time: Damage to the transmission's shift control mechanism; abnormal wear of gears and clutch plates inside the transmission; affect the normal operation of the transmission, leading to damage of the transmission valve body. Methods for replacing transmission fluid are as follows: Loosen the drain screw at the bottom of the transmission to drain the fluid before refilling. Remove the transmission oil pan directly for draining and refilling: This method is more thorough than the previous one, removing impurities from the bottom of the oil pan. Using a circulation machine to replace automatic transmission fluid: Dynamic fluid replacement with an intelligent circulation machine can filter and clean sludge and impurities inside the automatic transmission.
12
5
Share

Why can't the rear window of the 2021 Sagitar be fully lowered?

Most car rear door windows cannot be fully lowered to the bottom, leaving a section of the glass exposed. This is mainly due to the influence of the rear wheel arch shape, which results in insufficient space inside the door for the entire glass to retract. This is a normal phenomenon and not a malfunction. Here are some additional details: 1. If you notice that your car's rear window cannot be fully lowered, this is normal and there is no need to worry too much about it. 2. The door shape can only be designed with a semi-circular lower edge, while the glass is rectangular, making it impossible to fully lower. Many cars are designed this way. Car windows offer more advantages than disadvantages to the owner. For example: the owner can achieve better air circulation by opening the car windows, and it can also reduce odors inside the car. Of course, the windows also allow people inside the car to see the outside scenery.
2
4
Share

What kind of engine oil is suitable for the Changan CS55?

Changan CS55 can use synthetic engine oil, and the recommended oil filling amount is about 4L. Relevant information is as follows: 1. Engine oil consists of two parts: base oil and additives. The base oil is the main component of lubricating oil, determining its basic properties. Additives can compensate for and improve the shortcomings of the base oil's performance, giving it certain new properties, making them an important part of lubricating oil. 2. The Changan CS55 is equipped with a turbocharged engine. The headlights present a sharp design style, and the polygonal grille is paired with silver trim, giving the front of the car a strong sense of power. The car's body dimensions are 4500mm in length, 1855mm in width, and 1690mm in height, with a wheelbase of 2650mm, making its body size moderate in its class.
15
3
Share

How to Replace the Air Filter for Haval H6?

Haval H6's air filter replacement process is as follows: 1. Open the glove compartment, locate the buckle lever and pull it out. Use both hands to squeeze the sides of the glove compartment inward to remove it. 2. After removing the glove compartment, you can see the air filter. Simply pull out the old air filter and install the new one. 3. Reinstall the glove compartment and finally secure the buckle lever. Generally, the air filter should be cleaned and maintained after driving 7,500-8,000 kilometers. However, environmental conditions vary by region. It's worth noting that in areas with heavy dust, the maintenance interval should be significantly shortened to extend the air filter's lifespan.
8
5
Share
Cookie
Cookie Settings
© 2025 Servanan International Pte. Ltd.