The reason why the alarm will sound every few hours after locking the car is because the vehicle alarm cannot detect the front-end sensor or the front-end sensor sends an alarm signal, and the vehicle alarm will then sound an alarm.
For this problem, it is difficult for ordinary car owners to distinguish which abnormal noises are faulty and which are reasonable abnormal noises. If you go to a repair shop to check for abnormal noise, only nearly 20% of the cars actually have a problem. Models equipped with a turbocharged engine will make different noises than natural suction; models equipped with engine guards may also produce noise due to friction; some car owners may have lack of understanding of mechanical knowledge after being exposed to different cars. Mistaking reasonable abnormal noises for vehicle failure. Therefore, learn to identify abnormal car noises to avoid wasting time and energy.
Identification method of car noise:
In actual work, due to limitations of working conditions, it is difficult to use special instruments to measure the sound of cars. The only way to measure the sound in daily life is to Use judgment to describe and compare the sounds of cars. For example, the "squeak" sound made by dry friction of the bearing, the "click" sound made by excessive valve clearance, which is similar to the "click" sound of a small hammer tapping on the cement floor, etc.
1. Correctly distinguish between normal sounds and abnormal sounds.
When the car is working, the vibrations of various mechanisms will emit sounds of various natures, but the sound does not mean that the car is faulty. In order to avoid unnecessary disassembly, we must first distinguish between normal sounds and abnormal sounds. Normal sound. Normal vibrations of various system components (such as noise on the surface of the engine), impact sounds of gears when shifting gears, intake and exhaust sounds using gas as a working source, gear meshing noises, etc. are all normal sounds. Abnormal noises (abnormal noises) can be divided into slight noises, normal noises and malignant noises according to their impact on car performance. Slight noises, such as the flashing sound of high-voltage electric leakage, the slight loose sound of rolling bearings, etc., are generally small in volume, the degree of wear of the parts is not large, and there is no significant change for a long time. Such faults can still maintain the car without repair. of normal driving.
3. When diagnosing abnormal car noises, attention should be paid to creating good auscultation conditions and trying to eliminate interference from other noises so as not to affect the accuracy of judgment.
It is best to consciously amplify or reduce the sound, that is, use a screwdriver or other metal rod as a stethoscope to contact the sounding part to amplify the sound, or use a single cylinder to cut off the fire to reduce the sound. , to meet diagnostic needs. The auscultation site should be kept quiet to minimize human interference.