Quick Reference
- F17 — No water fill (inlet valve, taps, or low pressure)
- F18 — Drain error (pump filter blocked or pump failure)
- E01 / F34 — Door lock fault (latch broken or door not sealed)
- F21 / E3 — Motor fault (brush wear or control board)
- F36 / E43 — Door lock electronics fault (requires professional service)
- Repair cost: $150–$350 | $89 diagnostic — waived with repair
Bosch washing machines are renowned for their quiet operation and build quality, but when something goes wrong, the display shows error codes that can look confusing at first. Bosch uses both E-series codes (E01, E17, E23, E43) and F-series codes (F16, F17, F18, F21) depending on the model and generation. This complete guide explains every code, its likely cause, and what to do about it.
Bosch Washer Error Codes — Complete Table
The table below covers Bosch front-load washing machine error codes across all common GTA market models including the Serie 2, Serie 4, Serie 6, and Serie 8 ranges.
| Error Code | Meaning | Common Cause | Fix | DIY? |
|---|---|---|---|---|
| F17 / E17 | Water fill error — not enough water entering | Taps closed, kinked hose, clogged inlet filter, low pressure | Open taps, straighten hoses, clean inlet mesh filters | DIY |
| F18 / E18 | Drain error — drum not emptying | Blocked pump filter, kinked drain hose, pump failure | Clean pump filter, check drain hose, verify standpipe height | DIY |
| E01 / F34 | Door lock fault | Door not closed, latch broken, wiring fault | Ensure door is firmly closed; check for items in door seal; replace latch if faulty | Inspect First |
| F16 | Child lock active OR door open fault (model dependent) | Child lock activated; or door interlock fault | Hold child lock buttons 3 seconds to deactivate; or check door seal/latch | DIY |
| F21 / E21 | Motor speed fault | Worn motor brushes, motor control board failure, tacho sensor fault | Reset washer; if persistent, motor brushes or control board need professional service | Pro |
| E23 | Aqua-stop / leak sensor activated | Water leak in base of machine, hose connection loose | Turn off water supply; check hose connections; do not use until leak is fixed | Pro |
| E27 | Low mains voltage / power supply issue | Voltage drop, extension cord, circuit issue | Plug washer directly into wall socket on a dedicated circuit; check home voltage | DIY |
| E43 / F36 | Door lock electronics fault | Door lock control board or wiring harness failure | Professional replacement of door lock module required | Pro |
| E02 | NTC thermistor / temperature sensor fault | Faulty thermistor or wiring to thermistor | Professional thermistor replacement required | Pro |
| E03 | Heating element fault | Failed heating element, scale buildup on element | Descale machine; if code persists, element needs professional replacement | Pro |
| d01 | Drum rotation fault (diagnostic code) | Motor or drum bearing issue | Professional motor and bearing inspection required | Pro |
| d04 | Motor fault (diagnostic code) | Motor winding failure or tacho sensor issue | Professional motor diagnosis required | Pro |
| F22 | NTC sensor short circuit | Temperature sensor short-circuited | Professional NTC sensor replacement required | Pro |
| F25 | NTC sensor open circuit | Temperature sensor wire break | Professional wiring or sensor replacement required | Pro |
| F29 | No water detected during wash | Pressure switch fault, water level sensor failure | Reset washer; professional diagnosis of pressure switch if code returns | Pro |
How to Fix the Most Common Bosch Washer Error Codes
F17 / E17 — Water Fill Error
The F17 or E17 code is the most common Bosch washer error code seen in GTA service calls. It means the machine could not fill with enough water before the time limit expired.
- Check that the cold water tap (and hot tap if applicable) behind the washer are completely open.
- Straighten the inlet hoses — even a slight kink can reduce flow below the required rate.
- Unscrew the inlet hose from the back of the washer and locate the mesh filter inside the valve connection. Pull out the filter with needle-nose pliers and rinse under running water to clear sediment.
- Run the inlet hose briefly into a bucket to verify adequate water flow from the tap side.
If flow is good from the tap but the F17 code persists, the water inlet valve solenoid has likely failed and needs professional replacement.
F18 / E18 — Drain Error
F18 means the drum still has water in it that should have drained. Before calling for service, check the pump filter — this is the number one cause of F18 errors and is a simple DIY fix.
- Locate the pump filter access door at the lower front of the washer. Place a folded towel and a shallow container underneath.
- Open the door, slowly unscrew the drain hose cap and let water drain into the container, emptying it as needed.
- Fully unscrew the pump filter cap and pull it out. Remove all lint, coins, hairpins, and debris.
- Rinse the filter under running water, reinsert it, and screw the cap firmly closed.
- Check the main drain hose at the back for kinks. The end of the hose should be no more than 100 cm (39 inches) above floor level for proper drain height.
E01 / F34 — Door Lock Fault
Bosch washers will not start or continue a cycle if the door lock circuit detects the door is not securely latched. This protects against water leaking from an open door during a wash cycle.
- Inspect the door seal (rubber gasket) for coins, bra underwires, or clothing that may prevent the door from closing fully.
- Close the door firmly — you should hear a click as the latch engages.
- Try pressing the door firmly and starting the cycle. If the code clears, the latch is misaligned and may need professional adjustment.
- If the door clicks shut but E01 persists, the door lock solenoid or its wiring has failed and needs professional replacement.
E23 — Aqua-Stop Leak Sensor
Check all external hose connections at the back of the washer. If the connections are dry, the leak is likely from an internal hose or the drum seal — this requires professional diagnosis. Once the leak is repaired, the base of the machine must be fully dried out before the Aqua-Stop float can reset.
F21 / E21 — Motor Speed Fault
This error indicates the motor is not reaching or maintaining the correct speed during the wash or spin cycle. On older Bosch models (Serie 2 and 4), worn carbon motor brushes are the most common cause and are relatively inexpensive to replace. On newer brushless DC motor models, the motor control board is more likely at fault — a more complex repair.
Bosch Washer Series — Code Differences
Bosch washing machines sold in Canada come in four series with slight differences in how errors are displayed:
- Serie 2 & 4: Primarily use E-series codes (E01, E17, E18, E23). Older indicator light models blink a pattern instead of displaying codes.
- Serie 6: Uses a mix of E and F codes. The display shows the code clearly with a brief description on some models.
- Serie 8: Uses F-series codes on the LCD display. The Home Connect app can provide more detailed diagnostic information for connected models.
When to Call a Certified Technician
Call a certified appliance technician for your Bosch washer when:
- The error code returns immediately after a reset
- E23 (Aqua-Stop) appears — a leak inside the machine is a safety issue
- F21 or E21 (motor fault) appears — motor and brush repairs require disassembly
- E02, E03, F22, F25 (thermistor or heating element faults) persist after reset
- The drum is full of water and cleaning the pump filter did not resolve F18
- d01 or d04 diagnostic codes appear — these indicate serious motor or drum bearing faults
Frequently Asked Questions — Bosch Washer Error Codes
F17 on a Bosch washer means the machine is not filling with water. Check that both water taps behind the washer are fully open, inspect the inlet hoses for kinks, and clean the mesh filters at the inlet valve connections. Low water pressure and a faulty inlet valve solenoid can also trigger F17.
F18 is a drain error — the washer could not empty the tub in the expected time. Clean the pump filter (located behind the access panel at the lower front of the machine), check the drain hose for kinks, and ensure the drain hose is not inserted too far into the standpipe. If the pump is humming but not draining, a foreign object may be blocking the impeller.
E01 on Bosch washers typically indicates a door lock fault — the door is not locked or the lock mechanism has failed. Check that the door is closed firmly and there is no laundry caught in the seal. If the door appears to close properly but E01 persists, the door lock assembly needs professional replacement.
d01 and d04 are diagnostic service codes on some Bosch models, not consumer-facing error codes. d01 typically indicates the drum has stopped unexpectedly, while d04 relates to a drum motor fault. Both require professional diagnosis and are not DIY repairs.
F16 means the child lock is active on some Bosch models, or on others it indicates a door fault. If it is a child lock, press and hold the appropriate button combination (usually two buttons simultaneously for 3 seconds — check your manual). If it is a door fault, check the door seal and latch.
Turn the programme selector dial to the Off position, then unplug the washer from the wall outlet. Wait 60 seconds, plug back in, and turn the dial to your desired programme. This clears most temporary electronic fault codes. If the code returns, a component has failed and needs professional service.
Bosch washer repairs in the Greater Toronto Area typically cost $150–$350 depending on the fault and required parts. Nick's Appliance Repair charges an $89 diagnostic fee waived when you proceed with the repair, plus $40 OFF any repair with our current promotion.