To reset the 2004 Audi TT service interval after an oil change, please follow these instructions:

Manual Reset using DIS and Reset Knobs:
1. Turn off the ignition
2. Locate the Driver Information System (DIS) in the instrument panel.
3. Do the following to display the SERVICE! message in the display.
i) Press and hold the right RESET knob.
ii) Turn on the ignition – do not start the engine.
iii) Release the knob.
4. Do the following to display the next service interval (SERVICE IN ##MI)
i) Press and hold the right RESET knob.
ii) Release the knob.
5. Turn off the ignition.
6. Start the engine and verify indicator has been reset.