At first glance, it’s easy to assume that dishwashers only have parts that circulate water to wash dishes. While that’s true, Bosch dishwashers and many others also have heating elements inside to help with the drying process. That’s why your Bosch dishwasher might display an E09 error code.
The E09 error code on a Bosch dishwasher is caused by a burnt-out heating element. The element itself might have failed, or the control board has failed and isn’t supplying the heating element with any power. If the error code appears alongside the salt LED (on some models). In that case, it’s also possible that the root cause is a dirty salt sensor sending the wrong signals to the dishwasher.
In the following sections, we will look at the parts that cause the E09 error code on your Bosch dishwasher and what you can do to fix it.
What Does The E09 Error Code Mean On A Bosch Dishwasher?
On Bosch dishwashers, the E09 error code means that there’s a problem related to the dishwasher’s heating element. The code has the same meaning across all Bosch brand dishwashers, regardless of the model.
Suppose the E09 error code is on display at the same time as the salt LED. If that’s the case, then the problem might actually be a dirty salt sensor that’s mistakenly triggering the E09 code as well.
Related: 5 Common BOSCH Dishwasher Problems
1. Failed Heating Element
Like most brands of dishwashers, those by Bosch also have an electrical heating element inside. Typically, you’ll find the heating element located at the bottom of the dishwasher inside the washing compartment.
The heating element generates heat for several different reasons. Typically, the heating element helps to heat up the water that’s used to wash the plates, making the entire washing cycle much more effective.
Besides that, the heating element also helps to speed up the drying process once the dishes have already been cleaned.
As part of that, the heat generated by the heating element also helps to kill off any germs and bacteria, thereby sanitising the dishes before you take them out of the machine.
Why It Fails:
If the E09 error code is appearing on your dishwasher, it typically means that the heating element has somehow failed. To be precise, that means is that the heating element has burnt out for some reason.
The most common reasons for a burnt out heating element include water that’s found its way into the heater, a clogged drainage filter, or as the result of hard water and scaling.
In some cases, the heating element may have developed holes that allow water to flow inside. That could cause it to short out and burn.
Besides that, a clogged drainage filter could cause water to recirculate too slowly inside the dishwasher.
When that happens, it’s possible for the heating element to overheat, as there’s no water to help absorb that excess heat.
Lastly, if you live in an area that has hard water, scaling could occur on the heating element. That could lead to prolonged water heating and damage to the heating element.
If you have a multimeter at home, that could be very useful to diagnose the heating element and confirm whether or not it has failed.
A multimeter will help you test the continuity in the heating element, that is, to ensure that electrical current can indeed flow through the element as it should.
Besides that, you can also carefully inspect the heating element inch by inch to look for signs of burning or leaks. These will show clear signs on the heating element’s surface, helping you troubleshoot the issue much quicker.
How To Fix:
Generally, heating elements aren’t repaired, especially if they’re burnt. The more efficient solution would be to replace it.
To do that, begin by shutting off the water and power supply to your Bosch dishwasher. Then, refer to the user manual or technical sheet to locate and identify the heating element.
The resistance between the center and right contacts on the connector should be around 20 Ohms for European models and 10 Ohms for North American models. If you have infinite reading, the heater is burnt out.
You’ll need to disconnect it from its electrical connectors. To do this, you might first need to remove the front and bottom panels, depending on your Bosch dishwasher model and its design.
2. Failed Control Board Heater Relay
The control board is the ‘brain’ of your entire Bosch dishwasher. It’s a small printed circuit board that has plenty of electrical and electronic components on it.
Together, these components control and coordinate every action that the dishwasher takes, based on the settings you’ve chosen.
So, when you’ve loaded the dishwasher with your plates and cups and begin the washing cycle, the control board will then supply power to all the different components at the correct times.
That includes all of the appliance’s processes like washing, drying, and draining.
Why It Fails:
A failed control board can cause many problems, including those related to the heating element. For instance, one of the relays on the control board could have failed, resulting in no power being sent to the heating element.
As a result, the E09 error code appears because the heating element won’t turn on, even though it’s in good working order. In this particular case, the root cause of this issue is the control board that fails to provide power to the heating element.
Several factors can cause the control board in your Bosch dishwasher to fail. Among them is that an electrical surge has occurred and damaged the board, possibly due to a thunderstorm.
The same may also occur after a blackout when power is restored, and your dishwasher is still plugged in and turned on.
The control board is an electrical component. That means any water and excess heat can also damage it. Although less likely, it’s still possible that moisture and excess heat may have found their way towards where the control board is located, resulting in damage and malfunctioning parts.
Those two causes are more likely if your Bosch dishwasher is new or has been in service for a year or so. However, if your Bosch dishwasher has been in service for many years, then there is also one other possibility.
The control board may have failed simply because it has experienced too much wear and tear over the years, which is normal.
How To Fix:
The control board is yet another component that’s better replaced than repaired.
To do that, you’ll always want to shut off the power supply to the dishwasher to avoid injury and electrocution:
- Refer to the user manual and technical sheet to locate the control board. Typically, it’s located behind the control panel where you input your settings.
- Remove that panel, and you’ll find that the control board is held in place with screws that you’ll need to undo.
- Remove those screws and any electrical connectors the board has.
- Put in the replacement control board and then work backwards.
- Replace the screws, the electrical connectors, and then the control panel.
- Lastly, run a complete wash cycle to ensure that everything is working as it should.
3. Dirty Salt Sensor
Some Bosch dishwasher models also come with a salt sensor. As the name suggests, the sensor ensures that the dishwasher has enough salt to wash dishes efficiently.
Suppose your dishwasher is supplied with hard water that has lots of minerals in it. If that’s the case, the water may not be able to dilute the dishwashing detergent sufficiently . That’s why Bosch dishwashers also use dishwashing salt, which softens the water that comes into the appliance.
The salt sensor ensures there is enough salt to proceed with the washing cycle and warn the user whenever it’s running out. If your unsure how to refill the salt container, watch this video by Bosch:
Why It Fails:
Over time, the salt sensor in a Bosch dishwasher can get dirty. When that happens, the machine may wrongfully sense that the dishwasher has entirely run out of salt. The dishwasher then communicates this problem to the user by lighting up the salt LED on the control panel.
When that salt LED illuminates simultaneously as when the E09 error code appears, it’s possible that the problem isn’t caused by the heating element but is only a side effect of the dirty salt sensor instead.
How To Fix:
Depending on how severe the condition of the salt sensor is, you may need to either clean or replace the salt sensor. To do that, you must refer to the user manual and technical sheet to locate where it is and gain access to it.
- Typically, that involves removing the rear or bottom panel of the dishwasher. That’s because the salt reservoir is located at the bottom of the tub, not too far off from the drainage section of the dishwasher.
- As usual, disconnect the power and water supply to the dishwasher first.
- Then, you’ll want to remove any leftover water inside the tub to ensure that none of it comes splashing out when you’re working on the machine.
- Once you’ve located the salt sensor and gained access to it, remove its electrical connector and instal the replacement.
- Then, work your way backwards by replacing any panels you removed to gain access to it.