The Volvo XC90 displays a message on the dashboard display at regular mileage intervals to remind the driver to get regular engine oil changes. When a service technician performs the oil change, he resets the oil service light as part of the procedure. If you change the oil in the XC90 yourself, you can manually reset the service light. The procedure for resetting the oil service light is the same for every model year of the Volvo XC90.
Place the key in the ignition. Turn the ignition switch to the "I" position.
Press the trip odometer reset button. Hold the button down.
Turn the ignition selector to the "II" position.
Release the trip odometer reset button when the oil service light resets. This takes approximately 10 seconds.