The E09 error on your Bosch Dishwasher means the heating element or heating circuit has failed to reach the correct water temperature within the expected time. This is usually caused by a faulty heating element, a broken thermostat, or a wiring fault, and it often needs a multimeter to confirm before any parts are replaced.
| Error code | E09 |
|---|---|
| Meaning | Heating circuit fault — water not heating to the required temperature |
| Severity | Medium — the dishwasher may still run a cycle but with cold or poorly cleaned dishes |
| Time to fix | 20–60 minutes |
| Tools needed | Multimeter, screwdriver set, towel for water spillage |
What the E09 error means
E09 is triggered when the dishwasher's control board detects that the heating element hasn't warmed the water to the target temperature within a set time window. This is different from a "no power" fault — the machine is running, but the heating function itself is underperforming or has stopped working. It's one of the more common fault codes reported on Bosch dishwashers after a few years of use, since heating elements gradually wear out with mineral buildup and repeated heating cycles.
Common causes
- Heating element has burned out or developed a break in the coil
- Limescale or mineral deposits coating the element, reducing heat transfer
- Faulty thermostat or temperature sensor sending incorrect readings
- Loose or corroded wiring connections at the heating element terminals
- Control board fault misreading the temperature signal
- Low water level reaching the element, tripping a safety cutoff
How to fix the E09 error
- Power down and check water supply. Turn off the dishwasher at the wall, disconnect from the mains, and confirm the water inlet is fully open and not restricted.
- Inspect the heating element. Remove the lower rack and filter to access the heating element at the base of the tub. Check for visible cracks, scale buildup, or discolouration.
- Test element resistance with a multimeter. Disconnect the wires and test across the element terminals. A reading of infinity or zero ohms usually confirms the element has failed and needs replacing.
- Descale the machine. If the element looks heavily scaled but tests fine, run a dishwasher descaling product through a full cycle to clear mineral buildup.
- Check wiring and connectors. Look for loose, corroded, or burnt connections at the element and thermostat, and reseat or replace as needed.
- Reset the dishwasher. After any repair, power the unit back on and run a short cycle to confirm the E09 code has cleared.
If the fault persists after checking these areas, it's worth comparing troubleshooting steps used on other Bosch appliances — for example, diagnosing a Bosch Drill Won'T Start: Causes and How to Fix It follows a similar process of checking power, wiring, and internal components before replacing parts. Electrical faults across Bosch tools and appliances often share the same root causes, such as corroded connections seen in a Bosch Drill Battery Not Connecting: Causes and How to Fix It issue.
FAQ
Can I still use the dishwasher with an E09 error showing?
You can run cycles, but dishes may not be properly sanitised or dried since the water isn't reaching the correct temperature. It's best to fix the fault before regular use.
How much does it cost to replace a heating element?
Parts typically cost between £20 and £60, with labour adding more if you hire a technician. Many homeowners with basic DIY skills can replace it themselves in under an hour.
Will descaling always clear the E09 code?
Not always. Descaling helps if buildup is the cause, but if the element has actually failed electrically, it will need replacing regardless of how clean it is.
