Read the codes yourself. 2005+ models display all the engine/transmission/abs/vdc codes on the dash.
Just perform this sequence within 10 seconds:
1. Turn key to ON position (just before START)
2. Turn headlights ON
3. Press Trip button 4 times
4. Turn headlights OFF
5. Press Trip button 4 times
6. Turn headlights ON
7. Press Trip button 4 times
8. Turn headlights OFF (optional)
Codes will display in the trip meter. You might have to press the Trip button to cycle between engine, transmission, and braking computers.
The abs/vdc codes, at least, should be saved forever unless a dealer clears them.
This is a very nice feature of the 2005+ outbacks. My 2001 has three very different and complicated procedures for reading the engine, transmission, and braking codes. But it hasn't thrown any codes yet, so eh...