I had an issue where the laundry stopped working a few times (clicking baskets said no washing machine available, clicking the washing machine gave no menu options at all). Replacing the washer/dryer with a new one fixed it...but then it broke again a few days later.
I had to replace the washer/dryer 5 times over the course of a few sims weeks and determined that they stopped functioning any time my sims were away from the lot when the maid did her job. The washer would have the green light saying it was 'done' but be actually empty when I got home.
I put a door on the laundry room and locked it to everyone but household to keep the maid away from it...problem is now gone, for me. Errr...assuming I don't count having to do my own laundry instead of the maid doing it as a problem...