When a Bosch dishwasher quits mid-cycle and flashes a code, it’s handing you a diagnosis. A couple of these have real homeowner checks worth trying first. Most point at something a tech needs to handle. Here are the ones we see most, and the honest line between “try this” and “call someone.”
E24: it didn’t drain
E24 is the most common Bosch code we get called on. Two things to check yourself before anyone comes out.
The filter. Pull the lower rack, unscrew the cylindrical filter at the bottom of the tub, and lift out the flat mesh screen under it. Clean out any debris, grease, or glass, and run a short cycle. For most people, this is where E24 begins and ends.
The drain hose. It runs from the pump to your sink drain or disposal and needs a high loop or air gap to stop siphoning. If a disposal went in recently, confirm the knockout plug got removed from the inlet. Both are visual, no-tool checks.
Filter clean and hose fine but E24 persists? The drain pump is the likely culprit, and reaching it means laying the machine on its back and getting into the internals. That’s a tech job, and attempting it blind usually costs more than the service call would have.
E15: water in the base pan
E15 fires Bosch’s AquaStop protection when water hits the base pan. One thing to try: pull the unit out, tilt it back about 45 degrees, and let the standing water drain. Once the float switch resets, the code may clear.
If it keeps returning, there’s an active leak. Give the door gasket a look for cracks or debris and wipe it down. But tracing the real source (gasket, hose connection, inlet valve, spray arm) is diagnostic work, and getting it wrong means more water damage and a bigger bill. A tech pulls the unit, checks the base, and finds the leak properly. Don’t keep running it in the meantime.
E09: heating element fault
E09 means the board isn’t seeing the right signal from the heating-element circuit. Could be a burned-out element, a failed NTC temperature sensor, or a loose connection. Sorting out which one needs a multimeter and the expected resistance values for your exact model. There’s no safe home check here. Electrical testing on an unfamiliar machine leads to a wrong diagnosis more often than a fix, and the wrong part is wasted money. A tech tests the element and sensor, confirms it, and replaces the right one.
E22, E18, and the rest
E22 is a circulation fault, usually the same clogged filter behind E24. Clean it the same way. E18 is a water-supply issue: check that the valve under the sink is fully open. If pressure’s normal and the valve’s open, the inlet valve screen may be clogged or the valve is failing, which is a parts repair.
What’s actually worth trying
Filter cleaning, drain-hose inspection, confirming the supply valve is open, and the E15 tilt-and-drain. That’s the list. No tools, no disassembly. Anything past it, a failed pump, inlet valve, heating element, board, or internal leak, is a repair. Bosch machines are built well enough that fixing usually beats replacing, but a misdiagnosis costs more than just calling in the first place.
Book a service call
Worked through the basics and the code’s still up, or not sure what you’re looking at? Call us. We service Bosch dishwashers across the Bay Area, often same or next day. Schedule a visit at (925) 999-4095 and describe the code; we can usually tell you over the phone whether it’s a quick fix or a real repair. The $75 diagnostic is credited to the repair.