Error code reference

Bosch Dishwasher Error Code 2H

Last wash cycle too long (over 99 minutes); can be caused by cold inlet water or heating system fault…

Bosch codesBosch dishwasher codes

Last wash cycle too long (over 99 minutes); can be caused by cold inlet water or heating system fault (heater, Hi-Limit, flow switch, NTC, control module heater relay).

First step from the service manual

Check incoming water temperature and all heating system components.

The complete diagnostic procedure includes additional test steps, resistance specifications, wiring diagram references, and component test points.

MyPros+ Max

Get the full diagnostic procedure for 2H.

  • Step-by-step tests with expected resistance, voltage, and continuity values
  • Wiring diagram references and connector pinouts from the OEM service manual
  • Verified part numbers when replacement is required
Get the full procedure

$29/month · Cancel anytime · Or $9.95 3-day pass

What 2H means on a Bosch dishwasher

The 2H error code indicates the Bosch dishwasher control board detected that the last wash cycle exceeded 99 minutes, which triggers the code as a safeguard. The board monitors cycle duration and flags this fault when heating targets are not reached within the expected window. Root causes center on the heating circuit: a failed heating element, a tripped or failed Hi-Limit thermostat, a malfunctioning flow switch preventing the heater from activating, a faulty NTC temperature sensor sending incorrect readings, or a defective control module heater relay that fails to energize the element. Cold incoming water can also extend cycle time enough to trigger the code without any component failure.

For homeowners, this means your dishwasher ran too long trying to heat the water during a cycle and gave up before finishing. The machine needs water to reach specific temperatures to move through its wash and rinse phases. If the water coming into the machine is very cold, or if the internal heating system cannot warm the water properly, the cycle drags on until the control board stops it and displays 2H.

Start by checking the temperature of your hot water supply at the kitchen sink. If it runs cold for a long time before warming up, run the tap until hot water arrives before starting a cycle. If the incoming water temperature is adequate, the fault lies in one of the heating system components and will require testing with a multimeter.

Source: manufacturer service documentation.

Common causes of 2H

  1. 01

    Cold incoming water supply

    Wiring / connection

    If the hot water supply line to the dishwasher is long or the water heater temperature is set low, the machine receives cold water and the heating element cannot compensate fast enough to meet cycle timing thresholds, triggering 2H without any component being defective.

  2. 02

    Failed heating element

    Part replacement

    The heating element is responsible for raising water temperature during wash and rinse cycles. A burned-out or open-circuit element means the water never reaches the target temperature, causing the cycle to time out and log 2H.

  3. 03

    Faulty NTC temperature sensor

    Part replacement

    The NTC sensor feeds water temperature data to the control board. If it reads incorrectly low, the board keeps commanding heat that may already be adequate, or it may never signal that the target temperature is reached, extending the cycle past the 99-minute limit.

  4. 04

    Tripped or failed Hi-Limit thermostat or defective control module heater relay

    Part replacement

    The Hi-Limit thermostat cuts power to the heater if the element overheats; if it trips or fails open, the heater will not operate at all. Similarly, if the heater relay on the control module fails to close, the element receives no power and the water stays cold, producing 2H.

See the test procedure for each cause

Frequently asked questions about 2H

What does the 2H error code mean on a Bosch dishwasher?
2H means the control board recorded that the last wash cycle took longer than 99 minutes to complete. The most common reasons are cold incoming water, a failed heating element, a faulty NTC temperature sensor, a tripped Hi-Limit thermostat, or a defective heater relay on the control module. The board stores this code after the cycle ends rather than stopping the cycle mid-run.
How do I fix the 2H error code on my Bosch dishwasher?
Start by running your kitchen hot water tap for 30 to 60 seconds before starting a cycle to ensure hot water reaches the machine. If the code returns, you need to test the heating element for continuity with a multimeter, check the NTC sensor resistance against Bosch specifications, and inspect the Hi-Limit thermostat and control board heater relay. A failed heating element or NTC sensor are the most common parts to replace and are DIY-accessible on most Bosch models if you are comfortable with basic appliance repair.
Can I still use my Bosch dishwasher when it shows 2H?
The dishwasher will generally still run cycles after displaying 2H, since the code is logged at cycle end rather than as a hard lockout. However, if the heating system is faulty, dishes are not being sanitized properly and heavily soiled loads will not clean well. Running the machine repeatedly with a heating fault can also cause the Hi-Limit thermostat to trip again or put additional stress on the control board. Address the root cause before continuing regular use.
How much does it cost to repair a Bosch dishwasher with error code 2H?
If the fix is simply preheating the water supply line, there is no cost. A replacement NTC temperature sensor typically runs $15 to $40 for the part. A new heating element for a Bosch dishwasher usually costs $30 to $80 in parts. A Hi-Limit thermostat is generally under $20. If the control module heater relay is the fault, the entire control board may need replacement, which can cost $100 to $250 for the part alone, making professional diagnosis worthwhile before purchasing that component.
Will resetting my Bosch dishwasher clear the 2H code?
A reset, typically performed by pressing and holding the Start button for 3 to 5 seconds or cutting power at the breaker, will clear the 2H display. However, if the underlying cause is not resolved, the code will return after the next cycle again exceeds 99 minutes. Use the reset to clear the code after you have addressed the root cause, not as a substitute for diagnosing the heating system.

Related Bosch dishwasher codes

All Bosch dishwasher codes
View all 240 Bosch dishwasher codes

78,000+ service manuals · 160,000+ error codes · 55+ brands

Get Started

$29/month · Cancel anytime · Or $9.95 3-day pass