Hi,

Turn the keyswitch On.
Pull out the floor inspection plate and rotate to get access to the controllers plugs.
Connect your Curtis handheld or laptop with Curtis software to the Traction controllers plug.
Go to Parameters > Combi AM Master > Hourmeter Settings > Maintenance Settings.
Change the "Reset Maintenance" to On. (When you change this parameter, it will toggle to On momentarily then switch Off again).
Turn the keyswitch Off.
Disconnect the Curtis handheld or laptop.
Wait at least 5 seconds before keying back On.
If the service light turned Off then the procedure has been completed correctly.

Any issues please go to the web site (BLey has shared these already... Thank you Appreciated). Hope this helps.