Bosch Dishwasher Error Codes: DIY Troubleshooting Guide

Symptoms: The cycle aborts right at the beginning, or the wash pressure fluctuates (the pump draws air).

Cause: A calcified flow meter turbine, a blocked inlet hose filter, or exceptionally low household mains water pressure (below 140 kPa / 20 PSI).

What to do: First, check your tap pressure and clean the inlet filter screen. If the issue persists, the flow meter turbine can be removed from the side panel and soaked in white vinegar for 30 minutes to dissolve scale. As a last resort, the flow sensor board must be replaced.

Symptoms: The machine halts the cycle and displays the E25 error, leaving water in the sump. The control board detects an instantaneous spike in electrical current because the pump motor is completely seized upon activation, or it senses a total lack of hydraulic pressure.

Cause: A hard foreign object—such as shattered glass fragments, un-popped popcorn kernels, or toothpicks—has slipped past the filter and wedged the impeller blades tightly. The absolute most common cause, however, is human error: failing to securely re-seat the white plastic pump cover after routine cleaning, which prevents the pump from creating a vacuum.

What to do: Manually bail the standing water out of the sump with a sponge. Remove the filter array and carefully pry off the white plastic pump cover. Using protective gloves or needle-nose pliers, extract any binding debris from the magnetic impeller and verify it rotates freely. Crucially, reinstall the pump cover, pressing down firmly until it audibly “clicks” into its retention tabs.

Symptoms: Cold water circulates during the cycle, dishes remain greasy and wet, and the “Sanitize” or “Hygiene” light fails to illuminate.

Cause: A burnt-out heating element (often accelerated by hard water scale), damaged wiring, or a faulty relay on the main control board.

What to do: Multimeter diagnostics are required. Because the heating element is built into the pump, resolving this usually requires replacing the entire heat pump assembly.

Symptoms: The dishwasher becomes completely unresponsive to the control panel. The drain pump runs continuously with a persistent humming noise, even if you open the door, and the unit will firmly reject any attempts to start a new cycle or execute a soft reset.

Cause: Water has breached the internal seals and pooled in the base pan, triggering a highly sensitive expanded polystyrene (EPS) float switch. This can be caused by transient moisture (such as excessive foaming from using poor-quality detergent), a degraded plastic sump seal, a torn lower door gasket, or a leaky internal hose connection.

What to do: First, clear the immediate software lockout using the “tilt method”. Disconnect the dishwasher from the mains power point, pull the unit out slightly from the cabinetry, and carefully tilt it backward at a 30 to 45-degree angle to drain the trapped water onto a prepared towel. Once the water empties, the float switch will drop back down. Wait 5 minutes and restore power at the switchboard. Crucially, while this resets the machine, it does not repair a physical leak. If the E15 error returns during the next few washes, a systematic inspection to locate the leak and replace the perished seals is strictly required.

Symptoms: The wash cycle aborts prematurely, leaving the dishes wet and unrinsed. A pool of standing, often dirty water remains visible at the bottom of the tub above the filter. You might also hear a low-frequency hum as the pump struggles against an obstruction.

Cause: A physical restriction either within the machine’s primary filter or downstream in your household plumbing. Common culprits include a heavily soiled internal mesh filter, a clogged sink trap (S-bend), a kinked drain hose, failure to route the hose with a proper “high loop” under the benchtop, or an un-removed knockout plug in a newly installed food waste disposer.

What to do: Start by removing and thoroughly cleaning the cylindrical mesh filter at the base of the tub. Pull the machine forward to inspect the corrugated drain hose for kinks. Finally, disconnect the hose at the sink spigot to probe for fat or debris clogs, and ensure the hose is elevated properly under the sink.