What Causes the Engine Warning Light to Illuminate in a Van?
1 Answers
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 connections, or experience signal interruptions, the vehicle's ECU cannot accurately obtain engine data, triggering the engine warning light. Fuel or oil quality issues: Failure to use the fuel or oil specified by the manufacturer may cause engine wear, leading to the illumination of the warning light. Poor combustion of the air-fuel mixture: Poor combustion can result in engine carbon buildup or knocking. When detected by the oxygen sensor and reported to the ECU, the warning light will illuminate as a warning. Issues such as faulty spark plugs, ignition coils, fuel pumps, or clogged fuel lines can cause poor combustion. Turbocharging problems: Issues with the intake boost pipes or turbocharger can also trigger the engine warning light. The most common problem is a damaged turbocharger, 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 is compromised, it may lead to engine pipe blockages, and in severe cases, the engine warning light will illuminate. A dirty or uncleaned air filter can cause intake issues. Exhaust problems: Exhaust system faults can also cause the engine warning light to illuminate. Common causes include faulty rear oxygen sensors, catalytic converters, exhaust camshafts, or bearings. The catalytic converter is the most frequent culprit, often due to the use of leaded gasoline, lead or silicon-based oil additives, physical damage, or fuel system malfunctions. Anti-theft system malfunction: If the vehicle's electronic anti-theft system fails or the anti-theft controller does not match the engine ECU, the anti-theft system may prevent the engine from operating normally, accompanied by the illumination of the engine warning light. If the engine warning light illuminates, follow these steps: First, check if the engine is running normally. Look for symptoms such as shaking or black smoke. If present, avoid restarting the engine. Note: Never restart the engine if the light is red. If the engine can start, turn it off for 5-10 minutes. Then, without pressing the brake, press the start button or turn the key halfway to the "ON" position (without pressing the clutch). The vehicle will enter self-diagnosis mode. After 5-10 seconds, check if the warning light turns off. If the light remains on, visit a service center as soon as possible. Technicians can use a diagnostic tool to read the trouble codes and identify the issue for targeted repairs.