Bosch dishwasher not sanitizing

I’m new here – so forgive me if my question is answered elsewhere and I haven’t found it!
The “sanitized” button on my Bosch dishwasher isn’t lighting. And the dishes are wet, but seem clean, after the cycle.
I haven’t been able to find an owners manual online for my model so that’s my first ask – any idea where I might find one?
Second, how long should a dishwasher last? We installed this one probably in 2003. I don’t want to buy a new one …
Thanks!

Whoops – I forgot to ask – I’ve seen references to a “self test” but they seem to vary from model to model. Can’t find one for my model. That’d be a good place to start!