A dishwasher almost never fails in one step. It washes a little worse, or runs a little longer, or leaves a little water behind, and it does that for months while the household adjusts around it. The useful thing is that each of those three complaints points at a different part of the machine, and they are worth telling apart before anything is ordered.
Poor wash results
White film on glassware is the symptom everybody notices and it is the least mechanical one — it is a detergent, rinse-aid and load-pattern conversation more often than a repair.
Genuinely poor washing has a geometry behind it. Each spray arm jet is sized and angled to produce a particular pattern, and the classic report is that the upper rack comes out clean and the lower does not, or the reverse depending on which arm has stopped doing its job. So the sequence is: does each arm spin freely by hand; is the bearing or the hub worn enough to let the arm sit low and foul the rack; are the jets clear; is the mid-level feed to the upper arm blocked or split; and is the machine actually filling to the level it expects.
That last one is where a surprising number of these end. A machine filling short washes badly with every other part in perfect order, and the cause is usually the inlet screen, the fill valve, or a supply line kinked behind the machine when it was pushed back into the cabinet.
Cycles that have got longer
A control that is waiting on temperature will simply wait. Wash and rinse stages are gated on a thermistor reading, not on a clock, so anything that slows the water reaching temperature stretches the cycle instead of tripping a fault.
The candidates, in the order we check them: the incoming supply temperature itself; the wash thermistor and its wiring, where a connector corroded at the crimp reads low and the machine chases a temperature it already has; the heating element and its continuity and earth-leakage; and the circulation pump, because a pump moving less water heats it more slowly and washes worse at the same time.
A cycle that has stretched by a few minutes over years is worth investigating early, because at that stage it is usually a thermistor or a connector rather than an element.
Standing water at the end
Water in the sump at the end of a cycle is a drain fault, and the order is filter, sump, drain pump impeller, then the check valve, then the hose run, then the air gap or high loop under the sink.
Beach houses complicate the last two. Where the kitchen sits on a raised slab or above grade, the drain run to the disposer is often longer and flatter than it should be, and a partial blockage that would still clear on a short fall will not clear on a long one. The machine is fine; the run defeats it. That is worth knowing before a pump is quoted.
A detergent cup still full at the end of a cycle is a different fault entirely: either the cup did not open, which is a latch or a wax motor, or it opened into a wash that had no water in it.
Doors, seals and alignment
Door seals in a coastal house live in year-round humidity and tend to distort before they harden. A leak at a bottom corner is usually the seal at the corner radius, sometimes a door pulled down by weight loaded onto it while open, and occasionally a hinge spring or cable that has stretched enough to change how the door closes.
Latch problems on a built-in are frequently alignment rather than a broken latch. Cabinet panels move with the seasons in a house this close to the water, and the strike is no longer where the latch expects it. Adjusting that is a better repair than replacing a working latch.
Honest limits
Two things we will say out loud. A dishwasher whose tub has cracked or whose frame has corroded through is not economic to repair, and we will tell you that rather than quote it. And where a fault is confined to a proprietary control we cannot source or explain, the manufacturer is the right call, not us.
The visit
$80 flat, credited toward the repair. It covers fill volume, wash temperature, spray arm pattern and bearings, drain performance, the filter and sump, and the door seal, hinges and latch. Written estimate before any work. Genuine OEM parts, 90 days on labour and 365 days on parts. Viking equipment only.