Error code reference
Bosch Dishwasher Error Code E:21
Sanitized LED flashes; caused by faulty heat pump wire harness or faulty heat pump motor winding.
Sanitized LED flashes; caused by faulty heat pump wire harness or faulty heat pump motor winding.
First step from the service manual
1
Check continuity between heat pump and power module. Measure heat pump motor winding resistance between any 2 terminals (should be ≈ 15.2 Ω @ room temp). If so, replace power module. If not, replace heat pump.
The complete diagnostic procedure includes additional test steps, resistance specifications, wiring diagram references, and component test points.
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E:21 on my Bosch SHXM78W55N
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Sanitized LED flashes
From Service Manual 878937, p.29:
1.Check continuity between heat pump and power module. Measure heat pump motor winding resistance between any 2 terminals (should be ≈ 15.2 Ω @ room temp). If so, replace power module. If not, replace heat pump.
2.Measure drain pump winding resistance at connector J7 on the main control. Expected: 12 to 16 ohms at room temperature.
3.Back-probe the pump driver output under load. Verify the board switches the pump at 120 VAC during the drain portion of the cycle.
Part 00620774
Drain pump
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- #KApexx display
- 0No faults detected during test program (SHU 4322/4326, SHU…
View all 240 Bosch dishwasher codes
- 0000Inverter error
- 0001Inverter error
- 0010Inverter error
- 0011Inverter error
- 0100Inverter error
- 0101Inverter error
- 0110Inverter error
- 0111Inverter error
- 1Control module has timed out due to an unidentified heating…
- 10Functional safety error without remanence; last status LEDs…
- 1000Inverter error
- 1001Inverter error
- 1010Inverter error
- 1011Inverter error
- 11Synchronisation error; power frequency error or low voltage.
- 1100Inverter error
- 1101Inverter error
- 1110Inverter error
- 1111Inverter error
- 16Water switch fault detected during test program (on 2 &…
- 2Heating system fault during test program
- 2HLast wash cycle too long (over 99 minutes); can be caused…
- 3Door open after program start.
- 4Unexpected heating detected (heating is taking place at a…
- 5Water intake period exceeds 5 minutes.
- 6More than 7 pumping trials or pumping time exceeds 54…
- 7NTC short circuit or NTC open circuit.
- 8Water supply error; overflow level reached due to valve not…
- 9Aquastop triggered; water in base tub or wire harness…
- CFault SIBRUSYM-motor.
- Check water supplyThe device does not draw water; a continuous acoustic…
- CLCycle complete indication displayed at end of wash cycle.
- DNo BUS-communication with SIBRUSYM-motor.
- d:01Motor control short circuited
- d:02Motor control interruption
- d:03Damaged motor control temperature sensor
- d:06Motor control NTC relay failure
- d:07Motor control (inverter) failed or motor shorted
- d:08Motor speed sensor failed
- d:09Voltage too high
- d:10Power limiter switch off
- d:11Voltage too low
- d:12Motor control high current switch off
- d:13Motor control high temperature switch off
- d:14Motor control high temperature warning
- d:15Power limiter warning
- d:16Motor high temperature switch off
- d:17Motor high temperature warning
- d:18Peak voltage too high
- DOOR OPENDoor is not closed properly during the defined time period.
- Door open or won't lockDoor left open, faulty door latch, or faulty door lock
- dr:01IGBT short circuit
- dr:02IGBT interruption
- dr:03Damaged motor control temperature sensor.
- dr:06NTC relay failure
- dr:07Motor control (inverter) failed or motor shorted.
- dr:08Motor speed sensor failed.
- dr:09Voltage too high at motor control.
- dr:10Motor winding short circuit
- dr:11Voltage too low
- dr:12Motor control high current switch off
- dr:13Motor control high temperature switch off
- dr:14Motor control high temperature warning
- dr:15Power limit warning
- dr:16Motor high temperature switch off
- dr:17Motor high temperature warning
- dr:18Peak voltage too high
- E:00No errors detected; result of DW-internal testing.
- E:0000No error
- E:01Faulty relay to heat pump heater, or heat/drain pump…
- E:0100Internal fault power module
- E:0103Power module defect (internal pump control)
- E:0105Ground fault at Zeolite heater or relay for Zeolite heater…
- E:0106Ground fault at water heater
- E:0107Temperature monitoring
- E:0108D-Bus power limit exceeded
- E:02Faulty heat pump heater relay, ground fault at heat pump…
- E:03Overheated power module/power cord connection detected by…
- E:04Faulty safety heater relay on power module, ground fault at…
- E:05Water switch runs continually; Sanitized LED flashes…
- E:06Door ajar or not properly latched, door popped open, faulty…
- E:07Fan defective or blocked, module on the fan defective (only…
- E:08Too little water detected during heating; the programme…
- E:09Heating element open circuit / safety relay error; power…
- E:10Zeolite heater heating circuit interrupted…
- E:11NTC1 to NTC2 internal check failed; functional safety error…
- E:12Only one NTC returns a signal; the dishwasher shuts down as…
- E:13Incoming water temperature too hot (>75°C / 167°F)…
- E:14Faulty flow meter
- E:15Water in base / float switch activated and dishwasher runs…
- E:16Water supply (impulses from flow sensor) without activation…
- E:17Wash cycle abruptly stops, dishwasher drains continually…
- E:18Dishwasher waits for water filling, then wash cycle…
- E:19Loose/faulty harness to detergent actuator or faulty…
- E:20Sanitized LED flashes; caused by heat pump blocked/clogged…
- E:2012Heating circuit interrupted (resistance, supply wires…
- E:2030Heating element is calcified
- E:2040Wire or plug interrupted
- E:2050Safety relay heater defective
- E:2060NTC resistance values are outside permitted range
- E:2120Zeolite heater heating circuit interrupted…
- E:2130Heating fault
- E:22Sanitized LED is lit; caused by inlet water flow rate too…
- E:23Drain pump motor coil system check failed; functional…
- E:24Wash cycle completed prematurely, dishwasher won't drain…
- E:25Wash cycle completed prematurely, dishwasher won't drain…
- E:26Error code won't show during wash cycle; caused by faulty…
- E:27Low supply voltage continuously < 85 VAC (US) / 170 VAC (EU)
- E:28Aqua sensor doesn't run during wash cycle; error code won't…
- E:29Wash cycle abruptly stops or dishwasher won't run, or…
- E:30Dishwasher shuts off; error code won't show during wash…
- E:3000Filling fault
- E:31Poor washing and drying result due to rinse cycle without…
- E:3100Filling fault
- E:32Error code won't show during wash cycle. Caused by…
- E:3200No water supply at start of program or water supply flow is…
- E:3300Water supply flow is too high
- E:3400Water supply (impulses from flow sensor) without activation…
- E:6001Circulation pump fault
- E:6002Drain pump fault
- E:6101Open circuit to drain pump or resistance values of drain…
- E:6102Drain pump is blocked or drain pump cover in sump is…
- E:6103Non-return valve letting water by or draining is not…
- E:6900Dispenser or heat exchanger valve fault
- E:6A00Water switch fault
- E:8000Door Hall sensor fault
- E:8101Aquasensor fault
- E:9000Under/over voltage error
- E:9001Undervoltage fault
- E:9010Over voltage error (>142V)
- E:9240Zeolite fan defective or blocked, open circuit to Zeolite…
- E0Compartment temperature sensor 2 open/short.
- E01-00Defective electronics error, possibly related to power…
- E1Heating error
- E2NTC thermistor error
- E3Filling error
- E33Ice chute flap motor or switch error.
- E34Hopper flap switch error.
- E4Aquasensor error
- E5Safety float water level reached or motor speed error…
- E6Aqua sensor error
- E69-00Defective electronics error pattern.
- Er:01Door open
- Er:02Door lock cannot be released.
- Er:03Door lock cannot be locked
- Er:04Door actuation defective
- Er:05NTC interruption
- Er:06NTC short circuit
- Er:07Unexpected heating (temperature rise without actuating…
- Er:08Heating time exceeded
- Er:09No communication between control and inverter
- Er:10Flow meter gives wrong values
- Er:11Water inlet time exceeded
- Er:12Pumping time exceeded
- Er:13Safety level reached
- Er:14Overflow level exceeded.
- Er:15Pressure sensor gives failure voltage level
- Er:16Can't calibrate pressure sensor
- Er:20Spin cycle terminated
- Er:21Foam detected
- Er:22Frequency synch failure on control to mains
- Er:24Power supply relay to inverter damaged
- F00No faults registered in fault memory.
- F01Water/Heating NTC temperature sensor or leads…
- F02Water/Heating NTC temperature sensor or leads…
- F1Temperature stop fault
- F11Drainage fault
- F12Water intake fault at start of step
- F13Water intake fault at end of step
- F14Water intake fault
- F15Water intake fault
- F18Flow meter stationary state monitor
- F19Flow meter stiff and not turning freely
- F2Overfilling
- F24Heating relay contact fault
- F25Desired temperature fault
- F26Boiling protection
- F3Thermistor fault
- F4Water intake fault
- F40Electronic unit fault that cannot be repaired (e.g…
- F42Mains frequency registration fault
- F47Interface fault between selection-display module (BAE) and…
- F5Valve leakage
- F51Heater pressure switch fault
- F52Heater pressure switch has reset during heating
- F53Speed sensor fault
- F6Pressure sensor fault
- F63Slide shutter fault
- F67Circulation pump speed too low
- F68Circulation pump operation after switch-off
- F69Circulation pump blocked
- F7Pumping out fault
- F70Float switch fault
- F8Blocked filter
- F84Slide shutter positioning fault
- F85Slide shutter signal change fault
- F86Salt container lid contact fault
- F87Sensor softener fault
- F88Turbidity sensor fault
- F9Circulation fault
- F91Load size registration inactive
- FATurbidity sensor fault
- FBSpray arm divider fault
- FILTRCHGWater filter has been used longer than 6 months and needs…
- HIGHVOLTMains voltage is above the maximum limit (160V for US, 265V…
- LOWPOWERMains voltage is below the minimum limit (85V for US, 165V…
- MPower supply relay is defective, stuck together.
- Motor won't runFaulty speed control, triac short-circuited, or faulty…
- No drainingBlocked sensor, faulty water level controller, or…
- No heatingFaulty heater, voltage too low, or excessive scale on…
- No water fillingWater shut off, inlet strainer filters blocked, or water…
- Not drainingDishwasher did not drain within 5 minutes.
- Not fillingDishwasher did not fill after selected fill line was…
- Not HeatingWater temperature rose less than 9°F in 15 minutes during…
- NTC failedNTC thermistor short or open circuited, or faulty wire…
- OSafety level detected.
- Open or short circuit Door thermistor (Normal & Heat Dry)Temperature sensed was below 32°F or above 210°F on the…
- Open or short circuit Door thermistor (Normal/Normal)Temperature sensed was below 32°F or above 210°F on the…
- Oven TemperatureWater temperature sensed was greater than 180°F but less…
- OverfillLeak detection switch closed or 2nd level pressure switch…
- OverheatingFaulty control module causing heater to remain on when it…
- S3No faults detected (Apexx SH_99 full text display).
- TestNo heating
- Test (motor)Motor won't run
- Test (NTC)NTC failed (short or open circuited)
- Test (overheat)Overheating
- Turbidity Sensor High SignalTurbidity sensor count was greater than 65,279 in 0.4…
- Turbidity Sensor No Signal & Low SignalTurbidity sensor counter did not receive pulses from…
- Turbidity Temp SensorTurbidity temperature thermistor was shorted, open, or…
- WashDoor open or won't lock
- Wash (drain fault)No draining
- Wash (flashing)No water filling
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