Bosch Refrigerator Error Code E04
E04 appears on models fitted with a condenser temperature sensor in the freezer circuit, and it means that sensor has failed or its signal is out of range. Reset the power first; if the code returns, the sensor is a rear-compartment part and its replacement is a technician job.
Also shown as: E4
Common causes
- Condenser temperature sensor in the freezer circuit has failed or its signal is out of range
- Loose or damaged connection on the sensor wiring
What to check, in order
- Switch the refrigerator off and unplug it for at least 5 minutes, then restore power and see whether the code returns.
- Check that the ventilation clearance around the back and sides of the fridge matches your manual and that the vents are not blocked or pressed against the wall.
- If your manual shows the condenser area as user-accessible, brush or vacuum away heavy dust build-up. Never open any part of the sealed refrigeration circuit.
- If E04 returns after the reset, the sensor needs testing and replacement by a technician — on most models it sits in the rear machine compartment.
Clear the code and test
- Fix what the checks above found first. Clearing the code without fixing the cause only brings it back.
- Plug the appliance back in and restore its water supply if it has one.
- Run the shortest programme and watch the point where the code appeared before.
- If the programme finishes with no code, the fault is cleared. If the code returns, write it down before calling a technician — it speeds up the diagnosis.
When to call a professional
This code usually points to a faulty part, wiring or the control board on a Bosch refrigerator. Run the checks above to rule out the simple causes, then book a technician — and book one straight away if any of these apply:
- The code comes back after you have run the checks and a test cycle.
- You smell burning, see sparks or scorch marks, or the breaker trips.
- Water is leaking and you cannot stop it at the tap.
- The fix needs panels opened beyond what your manual describes, or a part tested with a meter, and you are not set up for that.
When you call, give the brand, the code E04, your model number (on a label inside the door or on the back) and the checks you already ran. It shortens the visit.
Repair or replace?
This fault is in professional territory: the fix usually means a major part or board-level work, and the labour adds up. If your machine is already well into its service life, get the repair quote first, then compare it with the price of a current equivalent model before you decide. Paying a large share of a new machine's price to repair an old one is rarely the better deal; replacing a machine over one cheap fault is wasteful too.
Parts that may be involved
Freezer condenser temperature sensor
Parts are model-specific. Find your model number first — usually on a label inside the door, on the door frame or on the back — and match the part to that number before ordering.
Questions people ask about E04
What does E04 mean on a Bosch refrigerator?
E04 means: Freezer condenser temperature sensor fault. E04 appears on models fitted with a condenser temperature sensor in the freezer circuit, and it means that sensor has failed or its signal is out of range. Reset the power first; if the code returns, the sensor is a rear-compartment part and its replacement is a technician job.
Can I fix Bosch E04 myself?
Only the preliminary checks. Code E04 usually means a part, wiring or the control board has failed, which is a technician job. Run the checks to rule out simple causes before you book.
How do I clear Bosch E04?
Fix the cause first — clearing the code on its own brings it straight back. Then restore power and water, run the shortest programme, and watch the stage where the code appeared. If the programme finishes with no code, it is cleared.
Sources checked
- Bosch Home (US) owner support: dishwasher error codes
- Coolblue advice: Bosch and Siemens washing machine errors
The meaning and checks for this code were checked against the sources above in November 2026. Codes vary by model and region; if your manual lists a different meaning for your exact model, follow the manual.