Land Rover Repair: 2001 Discovery SE Service Engine light, obd ii scan tool, engine management computer

Question
How do I turn off the "Service the Engine Soon" light?

Answer
On your car, the light is on because there's a problem with how your engine is running.  It may seem fine to you but the computer that runs your Rover's engine is quite sensitive and it's detected a malfunction.

You connect an OBD II scan tool to the diagnostic port under the dash

You read the stored fault codes from the engine management computer

You fix whatever problems are indicated by the stored fault codes

Once you've repaired the vehicle you clear the codes.