The Most Common Causes
These are the failure modes our technicians see most often on this symptom — listed in rough order of frequency. We don't publish step-by-step repair instructions for liability reasons, but the diagnostic process below identifies which one applies to your machine before any parts get swapped.
Clogged drain hose
Food debris, grease, and scale collect over years. Hose between the dishwasher and disposal or air gap blocks up.
Missing disposal knockout
When a new garbage disposal is installed, the knockout plug must be removed for the dishwasher drain to flow. If it wasn't, the dishwasher can't drain into the disposal.
Clogged sump filter
The filter at the bottom of the tub collects food bits. When it clogs, water can't reach the pump.
Failed drain pump
Motor or impeller failure. Pump runs but doesn't move water, or doesn't run at all.
Air gap clog
The countertop air gap collects debris. When it's blocked, water can't move past it. Cleaning is usually all it needs.
Before You Call — What's Safe to Try
Some of this you can absolutely handle, and we'll tell you straight which parts. Other fixes are doable but carry real risk, and a few you should never touch. This is general guidance, not professional advice — always unplug the appliance (or shut off the gas/water) before you check anything, and if it feels beyond you, that's exactly what the $50 Quick Check is for.
✅ Safe to try yourself
- Clean the filter. The cylindrical filter in the bottom of the tub is the #1 cause. Twist it out, rinse the food out, and replace it.
- Check the disposal knockout. On a new install, the plug in the garbage-disposal inlet must be knocked out, or the dishwasher cannot drain. Run the disposal too.
- Clear the drain hose. Make sure the hose under the sink is not kinked or clogged at the high loop.
⚠️ Doable — but know the risk
- Drain pump or check valve. A jammed or failed drain pump is replaceable, but means pulling the unit and disconnecting water.
🛑 Call a pro — don't touch this
- Control board
- Wiring
The Honest Answer
Yes — every scenario. Cleaning and unclogs are the cheap end ($150). Drain pump replacement runs $250–$350. No scenario where a draining issue makes a dishwasher not worth fixing. Parts availability and labor complexity matter more than the age of the machine. A well-built ten-year-old appliance with an available part is often worth fixing twice. A newer unit with a discontinued board is the harder call. Our techs lay both options out side-by-side — repair cost vs. replacement cost — and let you decide. Try the replacement calculator for a quick framing, but every situation is different.
Where's My Model Number?
A real technician needs your model number to nail the diagnosis and bring the right part. Here's where it hides — snap a photo when you find it.
Need the Part? We'll Find It.
Tell us your model and what's wrong — we identify the exact part, confirm it fits, and ship it to your door or install it. No hunting for part numbers; that's our job.
The 4-Option Technician Decision Report
After your $50 Quick Check (or $100 in-home diagnostic), a real technician — not a chatbot — reviews your model, video, and symptoms. They build a Technician Decision Report with four honest options:
You pick which option works for you. No surprises, no hidden costs. We don't share specific part numbers — we source the parts ourselves and ship them directly to your door, so you never have to hunt for the right SKU.
What Will This Cost?
Pick the likely repair to see our flat labor price next to what most shops charge all-in. The exact part price comes after a quick diagnosis — you'll see the real number.
Real Numbers, No Mystery
Most repairs for this symptom land in the range below. The diagnostic confirms exactly which job it is before any quote — and the diagnostic fee credits toward your repair labor.
People Also Ask
Other Things That Could Be Wrong
Middle TN + Louisiana
Whether you're in Nashville or Hammond, the diagnostic process is the same. We service Middle Tennessee and Louisiana with six experienced technicians.
Outside the cities listed? Chat with Ant — we'll confirm coverage before you pay anything.
Chat with Ant — Get a Real Answer Today
Chat with Ant — tell us what's wrong, share a quick video and your model number photo, and a real technician will build your Technician Decision Report. No hold music, no guessing, no commitment until you see your options.