C1 on a GE dishwasher (you'll also just see water standing in the bottom) means the machine isn't draining in the time it expects. Most drain problems trace to something you can clear yourself. Here's the order a tech works it, cheapest first.
The most common cause. Food, glass bits, and grease collect in the filter at the bottom of the tub and block the drain path.
Check it: Remove the bottom rack, twist out the cylindrical filter at the tub floor, rinse it clean, and clear any debris in the sump underneath before reseating it.
If the drain routes through a sink air gap or a garbage disposal, a clogged air gap — or a disposal that was just installed with its knockout plug still in — stops the dishwasher from draining.
Check it: Clean the air gap on the sink (pop the cap, clear it). If a disposal was recently installed, confirm the knockout plug was removed.
A drain hose kinked behind the dishwasher or where it connects under the sink restricts the flow.
Check it: Check the hose under the sink and behind the unit for kinks or clogs and straighten/clear them.
If the filter, air gap, and hose are all clear but water still stands, the drain pump has likely failed.
Check it: If everything upstream is clean and it still won't drain, this is the tech diagnosis and pump replacement.
Almost always repair — most C1 codes clear for free by cleaning the filter or air gap, and even a drain pump is an affordable part plus flat labor.
In Middle Tennessee or the Baton Rouge area? We'll come to you, same-day. Anywhere else in the U.S.? Send a 10-second video, a real technician tells you exactly what's wrong for $50 (credited toward the repair), and we ship you the exact part. 24/7 — text, call, or upload anytime.
Clean the filter at the bottom of the tub and the sink air gap first — those clear most C1 / standing-water cases. Then check the drain hose for kinks. If it still won't drain, the pump needs a tech.
It's not draining — usually a clogged filter or air gap, a kinked drain hose, or (if a garbage disposal was just installed) the disposal knockout plug left in. Clear those before suspecting the pump.
Often nothing (a filter or air-gap clean) or an affordable drain pump if it failed. Your $50 Quick Check credits toward the repair.