just noticed my navi 'locking' up today. if i don't tap 'ok' in the disclaimer screen before it shuts itself off, it won't come back on...actually if i hit the voice command button on the steering wheel the screen turns on again, but you can't press the 'ok' to bypass it. consequently, i don't have control of my a/c...big pain to turn the car off and back on just to get things working.

anyone know about any diagnostics that can be run?