What is the reason for three warning lights appearing when the car's power is turned on?
2 Answers
When three warning lights appear after turning on the car's power, it is generally caused by the vehicle's self-check after startup, which is a normal phenomenon. However, if the lights remain on continuously, it indicates a vehicle malfunction that requires timely repair. Below is relevant information about major vehicle malfunctions: Sensor malfunction: Includes water temperature sensor, crankshaft position sensor, air flow sensor, intake air temperature sensor, oxygen sensor, etc. When these sensors are damaged, have poor contact, or experience signal interruption, the vehicle's ECU cannot accurately obtain engine data, which will then trigger the engine warning light. Engine malfunction: The most common engine issues include idle shaking, lack of power when accelerating, and overheating. Generally, owners cannot repair engine malfunctions themselves and must seek assistance from 4S shops for repairs.
Once when I turned on my car's power, three warning lights suddenly came on, which really startled me. At the time, the engine light, ABS light, and airbag light were all illuminated. Typically in such cases, the vehicle's self-diagnosis system detects multiple issues, which could be an engine control unit error, brake system malfunction, or airbag sensor problem. Multiple lights coming on simultaneously often indicate interconnection problems between systems, such as a central module failure or unstable power supply. The most common cause is battery issues—if the battery is old and has low voltage, it can affect the entire circuit, causing multiple sensors to give false alarms. It could also be due to damaged sensors, poor wiring connections, or system software errors. I believe safety comes first, especially since an illuminated airbag light means the protection system may fail in a collision, so this shouldn't be taken lightly. I recommend pulling over immediately to check basic items, such as whether the battery connections are secure or if there are any abnormal prompts on the dashboard. If you're unsure, it's best to visit a professional repair shop to read the trouble codes and pinpoint the exact cause. Regular maintenance and paying attention to these systems can help prevent such troubles.
