I have Dolphin diagnostic dx advantage robot (circa 2003 or mso) which was repaired by replacing the cord and the unit worked fine for about a month. Now the unit bef gins it's cycle and goes for a short while and then stops . I take it out of the water and restart it and the same thing happens. the pool repair guy who replaced the cord (no warranty) said it was the motor, but the motor runs and climbs, it just stops quickly on it's own . I feel it is a sensor of sorts that is causing the problem. Any ideas ? I am not a handy sort of guy.