What is the car engine warning light?

[DeRowan]

There are mainly 7 reasons for the engine warning light to illuminate: Sensor malfunction: The sensors mentioned here include coolant temperature, crankshaft position, air flow, intake air temperature, oxygen sensors, etc. When these sensors are damaged, have poor contact, or experience signal interruption, the vehicle's ECU cannot accurately obtain engine data, which triggers the engine warning light. Fuel/oil quality issues: If fuel and engine oil are not added according to the manufacturer's requirements, it may cause engine wear and trigger the warning light. Poor fuel mixture combustion: Poor combustion can lead to engine carbon buildup or knocking. When detected by oxygen sensors and reported to the ECU, the warning light will illuminate as an alert. Issues such as spark plug failure, ignition coil malfunction, fuel pump failure, or clogged fuel lines can all cause poor fuel mixture combustion. Turbocharger problems: Intake boost pipes or turbocharger issues can also trigger the engine warning light. The most common issue is turbocharger damage, often accompanied by symptoms like oil leaks, excessive oil consumption, reduced power, metallic noises, or blue/black smoke from the exhaust. Intake problems: If the vehicle's intake system malfunctions, it may cause engine pipe blockages, potentially triggering the warning light. A dirty air filter that hasn't been cleaned regularly can lead to intake issues. Exhaust problems: Exhaust system failures can also illuminate the engine warning light. Common causes include rear oxygen sensor failure, catalytic converter issues, exhaust camshaft or bearing failures, with the catalytic converter being the most frequent culprit. Using leaded gasoline, lead/silicon-based lubricant additives, physical damage to the catalytic converter, or fuel system malfunctions can all contribute to catalytic converter failure. Anti-theft system malfunction: If the vehicle's electronic anti-theft system fails or if the anti-theft controller doesn't match the engine control unit, the anti-theft system may prevent normal engine operation while illuminating the warning light. When the engine warning light illuminates, follow these steps: First, check if the engine is operating normally. Look for symptoms like shaking or smoke emission. If present, avoid restarting the engine. Note: Never restart if the red warning light is on. If the engine can be started, turn it off and wait 5-10 minutes. Without pressing the brake, press the start button once or turn the key halfway to the ON position (without depressing the clutch). The vehicle will initiate a self-check after powering on. Observe whether the warning light turns off after 5-10 seconds. If the light persists, visit a service center promptly. Technicians can use diagnostic tools to read trouble codes, identify the issue, and perform targeted repairs.