Hey guys... Mind if I butt-in on this one? First off, I am going to assume this is a DD603, not 306, because, theat number didn't exist.
So, first question, and an important one. Was the F1 on both drawers simultaneously, with a beeping and flashing of the backlight on both displays?
If so, that is a flood error.
If NOT, that is an internal electrical fault, usually of the opposite drawer as the one that was running while the F1 appeared.
Most common problem for the early DD603 units is the plastic link arms that support and tuck the hose/harness assembly break, fail, causing the lid not to come down fully and water to leak at the rear of the drawers. ALWAYS change these when you see them, regardless of good or bad. This is per a 2005ish Fisher Paykel bulletin. Part 528437
A few tips while diagnosing these units:
1. You need the product code to order parts or look up bulletins. On the DD units, it is the first 5 digits of the Serial Number. On other FP Appliances it is a separate number on the tag.
2. Always drill down the behavior up to the failure, "which drawer was running when it failed"
3. Always check for corrosion at the "Mains Filter Board", bottom of the cabinet in the rear. This supplies 120 VAC to the system, communicates with the door modules, powers lid motors when needed.
4. Stretch before servicing, call chiropractor after.