Hard water sits behind more of these complaints than any failed part does: mineral scale closes the spray-arm holes one at a time, and the fix is a toothpick and half an hour in vinegar. The free fix on this list is the slow one: clogged spray arm holes (mineral scale) takes about 30 minutes and no part needed [S1], and 5 of the 8 causes here sit in that same column. On a dishwasher the complaint is the machine runs a full cycle and the dishes still come out dirty, and it arrives in these words: dishes come out with food still stuck on them, glasses have a white film after the cycle, the top rack is always dirtier than the bottom or the machine runs a full cycle and the dishes are still greasy. Money enters the page only after those: the completed repairs behind this symptom run $300–$480 [S2], against a replacement from $600.
Do this first (free)
clogged spray arm holes (mineral scale) [S1]
high likelihood easy no part needed about 30 min
the top rack is always dirtier than the bottom dishes come out with food still stuck on them
The first thing the source tells you to check, and the reason the pattern is uneven: once even a few holes are blocked, water pressure drops and whole sections of a rack stop being rinsed. The arms twist or snap off in about two minutes; clear the holes with a toothpick, then soak the arms in white vinegar for thirty minutes to dissolve the scale that built up over months. In the source's Florida and Georgia service area the tap water is hard and mineral scale sits behind many cleaning complaints. After reattaching, spin the arms by hand: they must rotate freely and hit nothing. Free. S3 prices a completed spray-arm replacement at a $283 median across its own dishwasher jobs, which is the figure to compare against if clearing the holes does not bring the spray pattern back.
dirty filter and food trap [S1]
high likelihood easy no part needed about 15 min
dishes come out with food still stuck on them the machine runs a full cycle and the dishes are still greasy
FIX 2 in the source's list: the filter catches what the pump would otherwise recirculate, and once it is loaded the machine washes the dishes in the water it just used. It comes out without tools on most models and is rinsed under the tap; the source's guidance is to do this monthly rather than waiting for a symptom. Nothing to buy.
wrong detergent or no rinse aid [S1]
medium likelihood easy no part needed about 10 min
glasses have a white film after the cycle the machine runs a full cycle and the dishes are still greasy
FIX 3. The white film on glassware that the source keeps separate from food residue is usually the rinse-aid channel running dry or a detergent that is wrong for the water: powders and pods built for soft water leave a film where the water is hard. This is a consumable rather than a repair, which is exactly why it belongs in the free column before anybody opens the machine.
improper loading blocking the spray path [S1]
medium likelihood easy no part needed about 5 min
the top rack is always dirtier than the bottom dishes come out with food still stuck on them
FIX 4, and the one that explains a fixed pattern rather than random residue: a sheet pan or a bowl facing upward sits over the spray arm and shadows everything under it, and tall items in front of the detergent dispenser stop the door from opening. The diagnostic value is that the failure follows the loading, so a load that cleans and the next one that does not points here rather than at a part.
inlet water below the detergent's working temperature [S1]
medium likelihood easy not priced about 20 min
the machine runs a full cycle and the dishes are still greasy
FIX 5. Most powders and pods do not dissolve properly and cannot cut grease below roughly 120F at the tap, so the cycle finishes with detergent still in the cup and grease still on the plates. The source's check is the water at the kitchen tap before the machine fills; several machines also let you raise the wash temperature or turn on a hi-temp option, which costs nothing and tells you whether the heater is doing its job. If it is not, this stops being a free fix. Time basis: no published duration, book estimate.
the sources publish no figure for a dishwasher heating element on its own; S1 headlines the completed fix for this symptom at $348 and S2 prices the mechanical end of dishwashing repairs at $280-500 for a control board and $300-480 for a circulation motor
What a technician actually does
damaged door gasket letting the wash water out [S1]
medium likelihood moderate $140–$220 installed about 45 min
dishes come out with food still stuck on them
FIX 6, and the cause that also leaves a wet floor or a wet cabinet edge if you look for it. A gasket that has gone hard or torn lets water escape past the door, so the pump loses pressure at exactly the point where the spray arms need it. The source puts it in the fix-it-yourself column rather than the pro column, and S2 calls the gasket one of the cheapest repairs in a dishwasher. Check the seal for hardness, splits and a door that no longer closes with resistance.
S2 prices a worn door gasket as a completed job at roughly $140-220 installed, which is the figure used here; it publishes no part-only price
failing wash pump or circulation motor [S1]
medium likelihood advanced $300–$480 installed about 120 min
dishes come out with food still stuck on them the top rack is always dirtier than the bottom
The source marks this FIX 7 PRO: the machine fills, drains and runs a normal-length cycle, and the dishes are still dirty because the pump is not moving the water hard enough to reach the upper rack. It is the point where the six free checks have all been done and nothing changed, and the source's own diagnostic line is that if the free fixes do not solve it, the fault is the wash pump or the control board. Time basis: no published duration, book estimate.
S2 prices a circulation wash motor at $300-480 installed; no separate part-only figure is published
control board not running the full cycle [S2]
low likelihood advanced $280–$500 installed about 90 min
the machine runs a full cycle and the dishes are still greasy
The board is the second half of the source's either-or diagnosis, and the one that is easy to buy by mistake. A cycle that is visibly shorter than the panel says, a dispenser that never opens, or a wash phase that skips straight to drain is a control fault rather than a water fault. S2 warns against a phone quote for this one: a repair price given without seeing the machine usually means a board has been guessed at rather than tested.
S2 prices a control board at $280-500 installed and notes premium European brands run higher; no part-only figure is published
Repair or replace?
Do the six free checks before spending anything, and treat a fault that survives all six as a mechanical one. If the machine is under eight years old and the diagnosis is a pump or a board, repair it: $300-480 against $600-1,000 for a mid-range built-in plus $150-250 to install and haul the old one away is not close. Past ten years, with a board or a pump gone and a second fault likely, replacement wins, because the machine's remaining life is shorter than the part's. [S2]
- Typical completed repair: $300–$480 [S2]
- Comparable new unit: $600–$1,000 [S2]
- Plus install and haul-away: $150–$250 — about $750–1250 installed all in [S2]
- Planning life used for the decision: 10 years
- The break-even is the installation, not the part: a built-in dishwasher has to be unplumbed, slid out and a new one fitted under a countertop, which is why S2 prices $150-250 of labour and haul-away on top of a $600-1,000 unit. That is the number a $348 median fix is being compared against, not the sticker price of the dishwasher alone.
S1's repair-or-replace line puts the age where a control board or pump repair stops making sense at around ten years, because the components around the failed one are near the end of their lives too; the source does not publish a design life for the cabinet itself
Run your own quote through the calculator — the same half-of-new-price rule with your numbers.