When the total mileage of your car approaches the specified maintenance interval for the engine oil change, oil filter change, or other required services, the appropriate indicator will change from green to yellow. The indicator will change to red if it is not reset before you reach the mileage interval. The indicator marked SERVICE INTERVAL is to be used as a reminder that there are items in addition to the engine oil and filter that require service each 7,500 miles (12,000 km). See the Maintenance Schedule on page 56.
After the maintenance is done, be sure to reset the switch below the speedometer by inserting the ignition key in the appropriate slot. The color of the indicator will change to green and repeat its cycle.
CAUTION: Do not reset the maintenance indicator while driving.
It says nothing else.
The ignition key does nothing when merely inserted, and it clearly says that they can be reset prior to turning red. So the manual is incorrect in some way.