What is the reason why the car air conditioner only has wind at the 4th speed?
2 Answers
When the car air conditioner switch only has wind at the 4th speed, it is usually due to a burnt-out blower motor resistor. The details are as follows: Solution: Promptly visit the car's 4S shop or a repair shop to replace the blower motor resistor, which will resolve the issue of the car's heating system not blowing air properly. Automatic and Manual Air Conditioning: Both automatic and manual car air conditioning systems operate similarly when heating is turned on. They adjust the temperature by rotating the temperature control knob, with the red zone indicating higher temperatures. However, automatic air conditioning can set a specific temperature, and it will automatically adjust based on the interior temperature. Some drivers, fearing the cold, immediately turn on the heating as soon as the car starts, thinking it will quickly warm up the interior, but this method is not very effective.
I've been driving for over a decade and have encountered situations where the AC only blows air at the fourth speed setting. This is mostly caused by a faulty blower motor resistor. The blower motor resistor controls the speed of the AC blower, just like a fan speed controller, adjusting the wind speed in low, medium, and high settings. If the components inside the resistor are damaged or burnt out, the circuits for low and medium speeds are cut off, preventing current from passing through, hence no airflow. Only the fourth speed (highest setting) works because it's directly connected to the battery, bypassing the resistor section. This issue is particularly common in older cars, especially during seasons with significant temperature changes, as the resistor components age quickly. Additionally, poor wiring connections or blown fuses can also cause similar problems. I recommend checking the fuse box and the fan switch connections immediately for any signs of looseness or damage. If you're not familiar with repairs, take it to a 4S shop as soon as possible to avoid minor issues turning into major motor repairs. Regular maintenance, such as cleaning the fan components, can help prevent such problems.
