What are the reasons for the engine warning light in older BYD F3 models?

[LeChristian]

The engine warning light may illuminate due to the following 7 main reasons: Sensor malfunction: This includes sensors such as coolant temperature, crankshaft position, air flow, intake temperature, and oxygen sensors. When these sensors are damaged, have poor contact, or experience signal interruption, the vehicle's ECU cannot accurately obtain engine data, triggering the warning light. Fuel quality issues: Failure to use the manufacturer-recommended fuel and engine oil may cause engine wear, leading to the warning light activation. Poor fuel mixture combustion: Incomplete combustion can cause engine carbon buildup or knocking. When detected by oxygen sensors and reported to the ECU, the warning light will illuminate. Potential causes include spark plug failure, ignition coil issues, fuel pump malfunction, or clogged fuel lines. Turbocharging problems: Issues with intake boost pipes or turbochargers (most commonly turbocharger damage) can trigger the light. Symptoms may include oil leaks, excessive oil consumption, reduced power, metallic noises, or blue/black exhaust smoke. Intake system problems: Clogged engine pipes due to dirty air filters (not cleaned regularly) may eventually cause the warning light to activate. Exhaust system faults: Problems like rear oxygen sensor failure, catalytic converter issues (most common), or exhaust camshaft/bearing failures can illuminate the light. Causes include using leaded gasoline, improper lubricant additives, physical damage to the catalytic converter, or fuel system malfunctions. Anti-theft system failure: Malfunctions in the electronic anti-theft system or mismatches between the anti-theft controller and engine ECU may prevent normal engine operation while activating the warning light. When the engine warning light appears, follow these steps: 1. First check if the engine operates normally. If there's shaking, black smoke, etc. (especially with a red light), do NOT restart the engine. 2. If the engine can start, turn it off for 5-10 minutes. Without pressing brakes, push the start button once or turn the key halfway to ON position (without clutch). After 5-10 seconds of self-check, observe if the warning light turns off. 3. If the light persists, visit a service center promptly. Technicians can use diagnostic tools to read trouble codes and perform targeted repairs.