What are the reasons for the reverse radar having display but no sound?
3 Answers
The reasons for the reverse radar having display but no sound are: 1. The buzzer is faulty; 2. The radar host wire is loose; 3. The buzzer circuit is faulty. The reverse radar consists of a host, display, probe, and buzzer. The probe is installed on the front and rear bumpers of the vehicle to better observe the parking distance. The full name of the reverse radar is reverse collision avoidance radar, also known as a parking assist device. It is a safety assist device when parking or reversing a car, which can inform the driver of the surrounding obstacles through sound or more intuitive display. It relieves the driver's troubles caused by looking around when parking, reversing, and starting the vehicle, and helps the driver eliminate blind spots and blurred vision defects, improving driving safety.
Last time my car had the same issue - the reverse camera showed grid lines but no beeping sound at all. First I checked the radar speaker in the trunk lid and found a loose connector. These small speakers are usually installed behind the trunk liner or at the rear of the car - try tapping it to see if there's any response. If you've modified wiring or removed interior panels, chances are the connector was forgotten. Another less common possibility: someone accidentally turned off the parking sensor audio in the vehicle settings - my neighbor's car had its sensors mysteriously muted in the infotainment system. Moisture is electronics' worst enemy - in humid southern climates, speaker connectors can oxidize and cause poor contact. If all else fails, replacing the speaker only costs around 100 yuan.
My old car had a similar issue where the reversing camera worked fine but the radar suddenly went silent. The mechanic demonstrated to me that using a multimeter to test the radar host output showed current fluctuations, indicating the system was operational. It turned out to be an aging buzzer—the small component that beeps inside the car. The mechanic said these typically last about five years. Another detail: if an aftermarket reversing camera is improperly wired in parallel, it can interfere with the original car radar's audio signal. Once, I carried a barrel of water that pressed against the trunk's inner wall and directly knocked the speaker loose. A tip: wipe the radar sensors when washing the car—dirt buildup can also cause strange malfunctions.
