Please could you help me my Bosch Dishwasher bought in 2011 keeps coming up with Error codes E14 and E18.There is water in the base of the dishwasher and does not complete the full wash cycle. I have put 2 lots of dishwasher cleaner through it and checked all of the incoming and internal filters and arms which are fine. Do I just need to replace the reed switch flow sensor and how do I do this? Thank you