What does the E2120 error code mean on a Bosch dishwasher?

The E2120 error code on a Bosch dishwasher indicates a water inlet or fill system fault. The dishwasher's control system has detected that the required water level has not been reached within the expected fill time, or that the water inlet valve is not responding correctly to control commands. The cycle is halted automatically to prevent the wash pump from running dry, which could cause permanent damage to the motor.

What is the difference between E2120 and E10 on a Bosch dishwasher?

E10 is a general water supply failure code found across a wide range of Bosch dishwasher models. It indicates that the dishwasher is not receiving enough water and is commonly caused by a closed supply valve, a blocked inlet hose, or low water pressure. E2120 is a more advanced diagnostic code specific to newer Bosch models that provides greater detail about the nature of the fill fault, pointing specifically to an inlet valve response failure, a water pressure issue below the appliance's minimum operating threshold, or a water level sensor fault that is incorrectly reporting fill status to the control board.

What causes the E2120 error on a Bosch dishwasher?

Common causes of the E2120 error include a faulty water inlet valve that is not opening fully or not responding to control board commands, water pressure from the household supply that falls below the dishwasher's minimum operating requirement, a clogged inlet valve filter screen restricting water flow, a faulty water level sensor or pressure switch that is incorrectly reporting the fill status, a kinked or partially blocked inlet hose reducing water flow rate, or a damaged wiring connection between the inlet valve and the main control board.

How do I fix the E2120 error on my Bosch dishwasher?

Start by checking that the water supply valve under the sink is fully open. Inspect the inlet hose for any kinks or bends and straighten if needed. Disconnect the inlet hose from the back of the dishwasher and clean the small mesh filter screen at the connection point to remove any debris or sediment restricting flow. Perform a hard reset by disconnecting power for 5 minutes and restarting. Check your home's water pressure to ensure it meets the dishwasher's minimum requirement. If the E2120 error continues after these steps, the water inlet valve, water level sensor, or associated wiring will need professional inspection and replacement.

Can I fix the Bosch E2120 error myself?

Basic checks such as opening the supply valve fully, straightening the inlet hose, cleaning the filter screen, and performing a hard reset can be done at home without special tools. However, if the inlet valve itself has failed electrically, the water level sensor is faulty, or there is a wiring issue between components, these repairs require disassembling internal parts of the dishwasher and working with electrical components. This type of repair is best carried out by a certified appliance repair technician.

How is E2120 different from E2030 and E2060 on a Bosch dishwasher?

E2030 is a flood protection fault triggered when water leaks internally into the base tray of the dishwasher, activating the AquaStop system. E2060 is a wash pump motor fault where the circulation pump is not operating within its expected electrical or mechanical parameters during the wash cycle. E2120 is a water inlet fault that occurs at the start of the cycle when the dishwasher cannot fill to the required water level. All three are advanced diagnostic codes found in newer Bosch models, but they affect different stages and systems of the dishwasher's operation.

Does Promix Appliance Repair fix Bosch dishwasher E2120 errors in Boston?

Yes. Promix Appliance Repair provides same-day Bosch dishwasher repair services throughout Boston, Newton, Needham, Brookline, Wellesley, and surrounding areas. Our certified technicians are experienced in diagnosing and replacing faulty water inlet valves, water level sensors, and wiring components on all Bosch dishwasher models including newer models with advanced electronic controls. Call (781) 666-9565 to book a same-day appointment.

E2120

Bosch · Dishwasher · Error Code

Bosch Dishwasher E2120 — Operation Module Cycle Completion Fault

Tech — Requires Professional Diagnosis Also shown as: E 2120 2120

Quick Answer

The E2120 error code means the operation module could not correctly close a wash cycle — the program logic reached the end of a cycle sequence but the machine's actual state did not match the expected end conditions. A hard reset clears E2120 caused by a one-time power interruption or software state mismatch. If the code appears repeatedly, particularly at the end of cycles, an underlying hardware fault is preventing the cycle from completing cleanly — drain pump, heating element, or a sensor feeding incorrect data — and professional diagnosis is needed.

Time

Technician visit

Difficulty

Professional only

DIY Steps

Hard reset only

Repair Cost

$0–$350

What the E2120 Code Means

Every Bosch wash cycle ends with a defined set of completion criteria: the tub must be fully drained, the water temperature must have fallen to a safe level, the drain pump must have confirmed a final drain, and the door lock must be in the correct state. The operation module checks each of these conditions before it closes the cycle and signals completion. E2120 is logged when this end-of-cycle handshake fails — one or more completion conditions were not met within the expected time window.

Where E2120 Appears in the Cycle

Pre-rinse

Fill → spray → drain

Main wash

Fill → heat → spray → drain

Rinse(s)

Fill → heat → spray → drain

Cycle close

Final drain → cool-down → unlock

E2120 logged here

The critical distinction is that E2120 almost always appears at or after the end of a cycle, not at the beginning or mid-wash. This sets it apart from other E20xx codes and is the key diagnostic clue: if the machine ran a full cycle and then displayed E2120 when it should have shown "Clean," the cycle completion check failed. The machine may or may not have fully drained, and dishes may or may not be clean depending on how far through the program the fault occurred.

Because E2120 is a consequence code — the operation module reporting that something wasn't right at the end — rather than a direct fault code, the underlying cause is often a separate hardware issue. A drain pump that doesn't fully empty the tub, a temperature sensor that keeps the machine waiting for cool-down, or a door lock that doesn't confirm its final state can all prevent the cycle completion check from passing.

E2120 in the E20xx Operation Module Family

E2030

Startup self-test fault

Operation module failed self-test before any cycle begins.

E2060

Program state inconsistency

Unexpected state detected during a live wash cycle.

This page

E2120

Cycle completion fault

End-of-cycle conditions not met — program could not close cleanly.

E2130

Module communication fault

Operation module lost contact with a sub-module mid-cycle.

Common Causes — Most Likely First

Power interruption during the final drain or cool-down phase. The cycle was nearly complete when a power event — outage, brownout, or door opening — interrupted the final steps. The operation module could not confirm completion and logged E2120. A hard reset and a fresh cycle clears this in most cases. Very common

Drain pump not completing the final drain. The tub retains residual water at end-of-cycle — the drain pump ran but could not empty the sump completely within the allowed time window. The operation module waited for a "tub empty" confirmation that never came. Common

NTC temperature sensor preventing cool-down sign-off. The temperature sensor is reporting that water is still above the safe end-of-cycle temperature when the cycle timer has already expired. The operation module is waiting for a cool-down confirmation the sensor cannot provide, either because it is faulty or the machine genuinely did not cool as expected. Occasional

Door lock not confirming final state. The door lock mechanism did not send its expected end-of-cycle confirmation signal. The operation module requires all safety systems — including the door lock — to report their correct state before closing the cycle. Occasional

Firmware or PCB memory fault. The control board's firmware has a corrupted end-of-cycle routine, or a PCB memory fault causes the completion check to fail regardless of the machine's actual physical state. More likely if E2120 appears on every cycle without any other hardware fault. Less common

What You Can Try Before Calling — Step by Step

Check for standing water in the tub

Open the dishwasher door and look at the tub floor. If there is visible standing water — even a shallow pool — the final drain did not complete. This is a significant diagnostic clue: it means E2120 was triggered by a real drainage failure rather than a software issue. Before a hard reset, check and clean the filter (twist counter-clockwise from the tub floor) and inspect the drain hose for kinks.

Standing water at cycle end points toward the drain pump or a blocked filter as the underlying cause. Also check the E03 drainage page for a more complete DIY walkthrough of drain fault checks.

Perform a hard reset — unplug for a full minute

Turn the dishwasher off and unplug it completely, or trip its circuit breaker. Wait a full 60 seconds. This clears the operation module's program state. If the cycle was interrupted by a power event at the final stage, the hard reset allows the next cycle to start from scratch with a clean state.

Run a complete cycle and observe the end behavior

Start a full wash cycle and stay nearby for the last 10–15 minutes. Pay attention to whether the machine drains fully at the end (listen for the drain pump running until quiet), whether the display transitions normally to "Clean" or "0:00," and whether E2120 appears at cycle completion again. Note the exact behavior for the technician.

Key observation: Does E2120 appear at the very end of the cycle, or during it? End-of-cycle appearance strongly points to a drain, temperature, or door-lock completion check failure. Mid-cycle appearance is more likely a firmware or communication issue.

Check the Home Connect app for companion codes

If your dishwasher is connected to the Bosch Home Connect app, check the diagnostic log after the failed cycle. E2120 frequently appears alongside a more specific hardware code — E03 (drain), E10/E14 (NTC sensor), or a door fault — that identifies the underlying component that prevented cycle completion. That companion code is often the more actionable fault to address first.

Book a professional diagnostic

If E2120 returns after a hard reset and a clean filter check, a technician needs to connect a Bosch diagnostic tool to read the full end-of-cycle error register. The sub-fault data identifies which specific completion condition failed — drain, temperature, door lock, or firmware — allowing the correct component to be addressed. This prevents unnecessary part replacement.

When to Call a Technician

Book service if any of these apply after a hard reset and filter check:

E2120 returns at end of the next cycle after a hard reset
Standing water remains in the tub at end of cycle — a drain fault is present alongside E2120
E2120 is accompanied by another fault code in the Home Connect app — the companion code identifies the hardware cause
The "Clean" light or end-of-cycle signal never appears — the cycle does not complete on any program
Cycles are completing but taking significantly longer than normal — the machine is waiting for a condition that is barely being met, suggesting a component nearing failure
E2120 appears on every cycle without variation — firmware or PCB fault rather than a hardware component

Repair Cost Expectations

Hard Reset / Filter Clean (DIY)

Free

If a power interruption or blocked filter caused the cycle completion failure, a hard reset and filter clean resolves E2120 at no cost. The most common outcome for a first-time E2120 occurrence.

Hardware Component Repair

$120–$350

Depends on the underlying cause: drain pump ($150–$280), NTC sensor ($110–$200), door lock ($130–$230), or PCB firmware reflash / replacement ($80–$350). Technician diagnosis identifies the correct component.

E2120 Recurring After Reset? We'll Find the Root Cause.

Same-day appointments across Boston. Certified Bosch technicians with factory diagnostic tools, common parts on the truck, and a 90-day warranty on every repair.

Book Bosch Dishwasher Repair Call (781) 666-9565

Frequently Asked Questions

Why does E2120 appear at the end of a cycle rather than the beginning?

E2120 is a cycle completion fault — it is generated by the operation module when the end-of-cycle checklist fails. The machine runs the entire wash program and then, at the final handshake before declaring the cycle complete, one or more conditions (fully drained, safe temperature, door lock state) are not confirmed. The fault is logged at that moment — at the end — rather than when the underlying problem first began. This is why E2120 is best understood as a symptom of a failing end-of-cycle condition, not the root cause itself.

Are my dishes clean if E2120 appears at the end?

Usually yes — the wash, rinse, and heated-dry phases typically completed before E2120 was logged at the final drain/cool-down check. However, the tub may not have fully drained, which means dishes could have residual water on them. Check for standing water in the tub and run a quick rinse cycle after clearing the filter if needed. If E2120 appeared mid-cycle rather than at the end, dishes may not be fully clean.

Can E2120 appear alongside other error codes?

Yes, and it frequently does. On connected Bosch models, the Home Connect app may show E2120 alongside E03 (drain fault), E10 or E14 (NTC temperature sensor), or a door fault code. The companion code is typically the actionable one — the underlying hardware issue that prevented cycle completion. Addressing the companion code often clears E2120 without any additional work on the operation module itself.

What is the difference between E2120 and E2060?

E2060 is a mid-cycle program state fault — the operation module detected an unexpected state while a cycle was running. E2120 is an end-of-cycle completion fault — the cycle reached its conclusion but the operation module could not confirm all end conditions were met. E2060 is more likely to be caused by a firmware or power issue mid-wash; E2120 is more likely caused by a hardware component (drain pump, sensor, door lock) that failed to confirm its state at cycle close.

How much does it cost to fix E2120?

A hard reset after a power interruption costs nothing. If the root cause is a blocked filter, cleaning it costs nothing. If an underlying hardware component needs replacement, cost depends on what failed: drain pump replacement runs $150–$280, NTC sensor $110–$200, door lock $130–$230, PCB firmware reflash $80–$120, or PCB replacement $220–$350 — all parts and labor in the Boston area.