Sprung leak when dishwasher was off

Hi - The other morning (more like 4 weeks ago) I woke to the Bosch dishwasher (SHX46A05UC) leaking. I shut off the hot water line and the leaking stopped. That morning was the first morning above freezing in 2 weeks. The floor below is poorly insulated. I'm guessing a line or part cracked because of freezing/thawing. Online forums suggest it might be a broken water inlet valve. What is the correct sequence to troubleshoot the problem? And how can I repair it myself? Thanks in advance for your advice and help.