What causes Service engine soon light to come on for Land Rover Discovery II?

The "Service Engine Soon" light on a Land Rover Discovery II can be triggered by various issues, including problems with the engine's emission system, faulty oxygen sensors, or issues with the fuel system. Other potential causes include a loose or damaged gas cap, issues with the ignition system, or a malfunctioning engine control unit (ECU). Regular diagnostic checks are recommended to identify the specific cause, as ignoring the light may lead to more significant problems.