Bosch · Dryer
Bosch Dryer E08 Error Code
Electronic control fault on heat circuit
What this error means
E08 is among Bosch dryer electronic fault codes tied to heat regulation electronics. The display may show E08 at cycle start or mid-dry when the board detects an invalid heat circuit signal—often after E01 or E12 airflow warnings were ignored.
How E08 is detected
When E08 appears on a Bosch dryer, the control board has confirmed that water did not leave the machine within the programmed drain window. On Bosch WQB245B0UC, Bosch WTG865H4UC, and similar variants, the drain pump runs for a fixed interval—often three to seven minutes on washers and dishwashers—while a pressure switch or turbidity sensor verifies the tub or sump is empty. If water remains, the cycle stops to prevent spin with a full tub or overflow on the next fill.
Most E08 calls are resolved without parts: turn off breaker thirty seconds and restore—single reset only. Restricted drain paths mimic pump failure because the impeller spins against a blocked hose or filter. Document whether the pump hums audibly during the drain step; a humming pump with no water movement points to a clogged filter or kinked hose, while silence may indicate a failed pump motor or loose wiring at the harness.
After clearing blockages, run a short cycle and listen at the drain hose for steady water flow. If E08 returns on the next load with a clean filter and straight hose, measure resistance at the pump motor connector per the service manual for your model before ordering a replacement pump assembly.
Common causes
- Control board heat driver failure after repeated thermal stress
- Communication error between UI and power board on heat-pump models
- Voltage drop on a shared laundry circuit during element engagement
- Prior E12 overheating event damaging board traces
Step-by-step fixes
- 1Turn off breaker thirty seconds and restore—single reset only
- 2Ensure lint filter and condenser are clean before retrying after E08
- 3Avoid extension cords or shared circuits with the washer motor
- 4Do not open rear panels unless qualified—capacitors hold charge
When to call a technician
Bosch groups E08 with codes requiring authorized service—board-level repair is not a typical DIY fix.
Affected models
- Bosch WQB245B0UC
- Bosch WTG865H4UC
- Bosch WTG86401UC
Prevention & maintenance
- Clean drain filters and hose terminations monthly on high-use dryers to prevent E08 from lint and food debris buildup.
- Record when E08 appears in the cycle and whether it clears after a 60-second power reset on your Bosch dryer—that detail speeds diagnosis if you call service.
- Keep the model and serial number from the rating plate when ordering parts for E08; Bosch uses multiple revisions with different harness lengths and board firmware.
- Photograph wiring connector orientation before disconnecting any component while troubleshooting E08; reversed plugs on pumps and valves cause immediate repeat faults.