Diplomat Dishwasher APG 8501?

We have inherited a Diplomat APG 8501 and there are two faults:
Shortly after the start of the cycle there is a loud rattling sound. This is caused by the internal tubes that circulate the water springing free from the base and is currently remedied by opening the door and plugging back into the fixture. Having done that the cycle carries on as normal. I've tried wrapping plumber's tape round the twin tubes at the bottom but to no avail.

The other problem is that there are occassions when all lights strat flashing. This indicates that there is no water in the machine and it is overheating. Whether the power would cut out before it bursts into flames I haven't tested.