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Why has the engine warning light come on?

Model: (Various brands) Various
Part: Warning light – error code

There can be various reasons why the engine warning light is on; today we will explain the four most common reasons: -The first reason the light is on relates to the sensor. The sensors for the crankshaft, camshaft, fuel delivery, mass airflow, and others ensure the engine operates correctly; if one of them fails, the engine enters a limp mode. -The second reason the light is on relates to a malfunction in the fuel system. The fuel pump delivers fuel from the tank to the fuel rail, through the feed pipe, and the injectors then spray the fuel into the combustion chambers. A failure in any of these components can lead to engine failure. -The third reason the light is on relates to faulty spark plugs or ignition coils. These components are involved in igniting the air-fuel mixture in the engine cylinders. In petrol engines, this mixture is ignited by an electric spark generated between the electrodes of the spark plugs; the coils then transform the low voltage into high. -The fourth reason the light is on relates to a faulty exhaust system. The oxygen sensor determines the amount of oxygen present in the exhaust gases and sends the data to the ECU. Based on this information, the air-fuel mixture is formed. If the catalytic converter is faulty, the light will come on. For all four reasons, to determine the origin of the fault, a computer diagnosis is necessary.

Updated on 8 September 2026 by ScegliAuto

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How to replace the horn on a Renault Duster - Dacia Duster

Today's main instructions will show you the procedure for removing and replacing the horn or sound signal on the Renault Duster, as well as the Dacia Duster. First, open the bonnet of the vehicle and start removing the front bumper by unscrewing all the fixing screws; you will find the horn right in front of the radiator, as shown in the video. At this point, disconnect the electrical connector and unscrew the bracket screw to remove and replace the horn with the new one; finally, reassemble the front bumper!

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by ScegliAuto

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