Bosch Dryer Error Codes — Complete E-Code Reference & Fixes

Bosch compact dryers (WTW heat pump and WGA condenser series) display error codes in the format E:XX when they detect a fault condition. These codes are your fastest diagnostic tool — each points directly to a specific subsystem. This guide covers every common Bosch dryer error code with its meaning, cause, and fix.

How to Read Bosch Dryer Error Codes

When an error occurs, the display shows the code (e.g., E:04) and the dryer stops or refuses to start. Some codes clear automatically after the fault resolves; others require manual reset (turn the program selector to Off, then back to a cycle).

To access stored error history on some models: Turn off dryer, then hold Start and a designated button simultaneously for 5 seconds to enter service mode.

Bosch Dryer Error Code Reference

E:02 — Motor/Drive Fault

Cause: The EcoSilence Drive motor is not responding to the control board. Could be motor failure, broken belt causing motor overload protection, or inverter circuit failure on the control board.

Diagnosis: Check if drum turns by hand (belt intact?). Listen for motor hum. If belt is fine and motor silent, the motor driver circuit has failed.

Fix: Replace belt ($25–$45) if broken. If belt is intact, test motor windings (should measure 3–8 ohms between phases). If motor tests good, control board motor driver section has failed ($150–$350).

E:03 — NTC Temperature Sensor Fault

Cause: One of the NTC temperature sensors reads out of range (open circuit or short). Bosch dryers have 2–4 NTC sensors monitoring inlet air, exhaust air, condenser, and drum temperatures.

Diagnosis: Access sensors (top panel removal, Torx T20). Measure resistance — each should read approximately 10–20 kohm at room temperature (NTC type). Open circuit (OL) or very low reading (under 1 kohm) = failed sensor.

Fix: Replace faulty NTC sensor ($15–$35 each). If all sensors test good, the control board ADC (analog-to-digital converter) may have a fault.

E:04 — Heat Pump Fault (WTW series only)

Cause: The heat pump compressor or refrigerant circuit has a fault. Commonly triggered by: lint-clogged condenser causing compressor overheat, refrigerant leak (no heating capacity), or compressor start failure.

Diagnosis: Clean the condenser first (pull out from front bottom, vacuum fins). If E:04 persists after cleaning, the compressor or its start relay has failed. Refrigerant system repairs require certified HVAC technician.

Fix: Clean condenser ($0). Replace compressor start relay ($30–$60). Full compressor replacement ($300–$600 + refrigerant charge).

E:08 — Condensate Tank Full

Cause: The condensate collection tank is full and must be emptied. Or, if direct-drain is connected, the drain path is blocked.

Diagnosis: Pull out and empty the condensate tank. If using direct drain, check hose for kinks and verify drain flows freely.

Fix: Empty tank or clear drain blockage. If the float sensor inside the tank is stuck (reports full when empty), clean or replace the float assembly.

E:09 — Communication Error

Cause: Communication failure between the main control board and the display/user interface board. Ribbon cable or connector issue.

Diagnosis: Remove top panel. Check ribbon cable connections between boards. Reseat all connectors. Look for corrosion on pins.

Fix: Reseat connectors ($0). Replace ribbon cable if damaged ($20–$50). If persists, one of the boards has a communication IC failure.

E:18 — Drain Timeout

Cause: The drain pump has been running for the maximum allowed time without successfully emptying the condensate. Pump is blocked, failed, or drain path restricted.

Diagnosis: Access drain pump (front lower panel). Check for lint/debris blocking the pump impeller. Verify drain hose path.

Fix: Clean pump impeller ($0). Replace drain pump if motor has failed ($45–$80).

E:23 — Door Lock Fault

Cause: The electronic door interlock is not engaging or not confirming engagement within the expected time.

Diagnosis: Listen for lock click after pressing Start. No click = interlock not receiving power or interlock mechanism failed.

Fix: Replace door interlock ($25–$60). Check wiring from board to interlock.

General Troubleshooting for Any Error Code

1. Record the exact code before resetting.
2. Power cycle: Turn program selector to Off. Unplug for 60 seconds. Replug. If code does not return, it was transient.
3. Clean the condenser — reduces thermal stress on many components.
4. Check for obvious issues: Full tank, blocked drain, loose door.
5. If code persists after reset + cleaning: Component replacement needed per code.

Error Code Quick Reference Table

When to Call a Professional

• E:04 that persists after condenser cleaning (refrigerant system — requires certification)
• E:02 with intact belt (motor/inverter diagnosis requires oscilloscope)
• Multiple error codes appearing together (board-level fault)
• Any code returning immediately after reset + component replacement

FAQ

Q: How do I clear a Bosch dryer error code?

Turn the program selector to Off. Wait 10 seconds. Select a new program. If the code returns, the underlying fault still exists. For stored codes in service history, a technician reset via service mode may be needed.

Q: My Bosch dryer shows E:04 but clothes are still damp. What failed?

E:04 indicates the heat pump is not operating correctly. Without the heat pump, the dryer cannot extract moisture effectively. Clean the condenser first — this resolves most E:04 occurrences. If the code persists, the compressor or refrigerant circuit has a fault requiring professional repair.

Q: Is E:08 a real problem or just a reminder?

E:08 simply means the condensate tank needs emptying. It is not a component fault. However, if E:08 appears with the tank empty, the float sensor is stuck — clean it or replace the tank assembly.

---

Bosch dryer showing an error code? Our technicians interpret codes and carry common replacement parts for WTW and WGA models. Schedule a diagnostic →