What does CEM mean in cars?

1 Answers
LeoAnn
07/29/25 11:36pm
CEM stands for the recirculation button, indicating the activation of air recirculation inside the vehicle. Introduction to External Circulation: External circulation refers to drawing air from outside the vehicle, directing it into the air conditioning system for heating or cooling, and then blowing it out through the vents. External circulation can replenish fresh air and improve the air quality inside the vehicle. However, if the outside weather is extremely dry and hot, using external circulation requires the air conditioning compressor to work continuously to cool the hot air from outside, which consumes a certain amount of fuel. Introduction to Internal Circulation: Internal circulation refers to the recirculation of air inside the vehicle. The air conditioning system draws in the interior air, cools it, and then recirculates it back into the cabin. When the interior temperature drops to the set value, the air conditioning compressor disengages, reducing the engine load. Therefore, the faster the interior temperature reaches the set value, the sooner the engine load is reduced, leading to a decrease in fuel consumption.
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