Soon i am wanting to do an oil and filter change but the oil service light hasn't come on yet. Is it possible to reset the counter on the AWS unit to coincide with the service or can it only be reset once the light comes on?
yes it is possible to reset. i read on here a couple of months ago that depending the year of your car on there is either a button in the glove box or a small hole on the AWS panel which you press with a pin or similar to reset.
The only way to do it is to disconnect the power to the AWS unit, just disconnecting the car battery overnight will do, or take the dash surround off , remove the AWS unit and disconnect the wiring plug overnight, this will reset the unit and take it back to 1 year or 10,000 miles, there is no internal battery as such in the AWS unit to retain its memory just a small capacitor which will keep it powered up for an hour or so.