Error E04 on a Bosch dishwasher

To resolve any dishwasher issue, you don't need to know the service phone number, but rather the error codes. This will help you avoid embarrassment, such as when your dishwasher displays error E04. This code means the appliance is unable to maintain the required pressure in the circulation unit. This is a critical issue, as it either prevents water from exiting the spray arms or does so without sufficient pressure to clean dirty dishes. Let's figure out how to fix this problem yourself.

Preparing for diagnostics

It's possible that the E04 error in your Bosch dishwasher is caused by a simple blockage, so this should be checked and fixed first. If you are unable to reset the error code in this way, you will have to partially disassemble the "home assistant" to conduct a quality diagnosis.

Never open the casing of a household appliance if the machine is still under warranty, as this action will void the warranty.

Once the warranty period has expired, you can begin work. Prepare a Phillips-head screwdriver, pliers, and a standard multimeter to check the functionality of the dishwasher's key components. Once the preliminary procedures are completed, you can begin disassembling the appliance.

• First, be sure to disconnect your Bosch dishwasher from all power supplies.
• Disconnect the inlet hose and drain any remaining liquid from the last working cycle.
• Disconnect the drain hose and inspect it for blockage.
• Secure the hose to the rear wall of the dishwasher using the fasteners provided by the manufacturer.

Now the machine can be moved to the center of the room to provide free access to all sides.

How much dirt is inside?

Often, the spray arms of a Bosch dishwasher stop spinning properly due to a clogged drainage system. First, you need to thoroughly clean the drain, and then examine the pump impeller. What should I do to completely clean the element?

• Make sure there is no water in the tank, and if there is any left over from the previous wash, it should be removed using the drain hose.
• Next, you need to remove all the dish baskets from the dishwasher bin.
• Remove the debris filter located at the bottom of the wash chamber.
• Locate the mesh filter installed directly below the debris filter and remove it as well.
• If the contamination from the filter is not removed because it has become embedded in the parts over time, you can use a citric acid solution in which the parts can be soaked for several hours.
• Remove any water that may have accumulated from the debris filter seat using a cloth or sponge.
• Remove the protective cover by pulling it towards you.

All described actions must be performed while wearing protective gloves to avoid accidentally cutting yourself on shards of broken dishes, which often get stuck in the impeller.

These steps will allow you to access the pump impeller, which is often the cause of the E04 error. Inspect the part for damage and carefully check for any foreign objects inside. Remove any glass fragments or other debris, and replace the impeller if damaged.

If the error code still hasn't cleared, you can try manually cleaning all the sprinkler nozzles with a toothpick or needle. This will take quite a bit of time, but it's necessary to resolve the water circulation issue.

One of the pumps is not working properly

If the E04 error code persists in your Bosch dishwasher even after clearing the blockage, the drain pump and circulation pump need to be tested. Let's start with the pump.

• Carefully remove the sprayer.
• Use a screwdriver to remove the bolts installed at the bottom of the washing chamber.
• Just in case, cover the floors with rags or unnecessary towels.
• Lay the dishwasher on its side.
• Remove the bottom from the appliance.
• Carefully disconnect the water level sensor wiring, which is attached to the bottom panel on the back side.
• Remove the electric motor wiring contacts.

Pay attention to the drain pump located on the side. You need to remove it and thoroughly clean the mounting area. Next, check the part with a multimeter. If the pump is damaged, don't try to repair it; it's easier to replace it with a new one. Purchase an original spare part that fits your Bosch dishwasher and install it according to our instructions, following all steps in reverse order.

A lack of spray arm rotation could also be caused by a damaged circulation pump. The procedure in this case is similar. If the pump motor hums loudly, but the "home assistant" doesn't turn on, and the sprinklers don't rotate, the problem is clearly with the motor. What should I do to test it and replace it with a new one?

• Loosen the hose clamps.
• Disconnect the connectors that supply power to the node.
• Using a screwdriver, release the latches.
• Carefully remove the mounting screw.
• Remove the fasteners of the other pipes.
• Carefully remove the motor and check it with the same multimeter.
• Replace the part if it is faulty.

If you want to avoid encountering the E04 error and other error codes in your Bosch dishwasher, try regularly cleaning the hoses and filters of any debris. This can be easily done yourself without calling a service technician, so it's worth performing this procedure at least once a month.

   

Readers' comments