Hi Ray, I didn’t get a response but I managed to figure it out. I found a service manual online and it said that error 15 is a ‘virtual sensor’ problem, which basically means reading between wash pump and drain pump not consistent. So one of these is either blocked or faulty.
After reading that I removed the main wash pump and found that in the chamber where the water is moved there was a load of stuff that resembled sand. I assume it was limescale as we live in a very hard water area. Cleaned it out, put it back together and it’s as good as new.
It wasn’t too difficult to do. I’ve never taken a dishwasher apart before this either. If you get stuck, give me a shout 🙂
Nick