Bosch dishwasher pump: how it works, why it breaks and how to fix it

Dishwasher Bosch is a complex unit where each element performs its own function. But if the heart of the technology is the electronic control unit, then its “lungs” are pump. It is he who is responsible for circulating water, pumping out waste fluid and maintaining pressure in the system. When the pump fails, the machine either stops washing dishes or refuses to turn on at all.

In this article we will look in detail at how the pump in dishwashers works. Bosch (including popular series SMV, SMS, SPV), what types of faults are there and how to diagnose them. And most importantly, we will tell you whether it is possible to repair the pump yourself, without resorting to the services of a service center.

It is worth noting that the design of pumps in machines Bosch latest generations (2018–2026) are somewhat different from older models. For example, in new versions it is often used brushless motor with electronic control, which is quieter and more reliable, but more difficult to repair. However, the diagnostic principles remain universal.

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Pump structure in a Bosch dishwasher

Pump (or pomp) in Bosch performs two key functions: water circulation during washing and draining waste fluid into the sewer. Most models use a combined design, where both processes are provided by one unit. However, in premium series (for example, Bosch Serie 8) there may be separate pumps for circulation and drainage.

Main pump components:

• 🔄 Impeller (impeller) - creates a flow of water. In models with EcoSilence Drive The wheel is made of composite materials to reduce noise.
• 🔋 Electric motor - drive mechanism. Budget cars use a brushed motor, while expensive cars use a brushless motor (for example, Bosch SMV88TX06R).
• 🛡️ Sealing gaskets - prevent leaks. They often fail due to hard water.
• 🔌 Hall sensor (in electronic pumps) - controls the rotation speed and transmits data to the control board.
• 🚰 Drain valve - opens to remove water. In cars with AquaStop the valve has additional protection against leaks.

In models Bosch with the system Zeolith (for example, SMV69T76RU) the pump works in tandem with a heat accumulator, which requires more precise pressure settings. If the pump in such a machine starts to “fail,” this can lead to errors E24 or E25 (related to water heating).

How are the pumps in the Bosch series different?

In budget series (for example, SMS24AW01R) a simple brush pump with a service life of ~5–7 years is used. In premium (Serie 8) there are brushless motors with a service life of up to 10–12 years, but they are sensitive to voltage drops. Also in expensive models the pump is integrated with the system PerfectDry, which makes it difficult to replace.

Signs of a pump failure

Pump failure rarely occurs suddenly; it is usually preceded by characteristic “symptoms”. If you notice at least one of the following signs, you should check your pump:

• 💧 The machine does not drain water — after washing, liquid remains in the tray, and an error appears on the display E22 or E23.
• 🔊 Extraneous sounds — the pump hums, creaks or makes “crunching” sounds (often due to broken glassware getting into the impeller).
• 🚱 Weak water pressure — dishes are difficult to wash, especially in the upper basket. This may indicate wear on the impeller or a clogged filter.
• ⚡ The machine knocks out the machine gun — when the pump is turned on, the protection is triggered (a sign of a short circuit in the motor winding).
• 🔄 The wash cycle is taking longer — if the pump does not create the required pressure, the machine repeats the rinsing steps many times.

Important: in cars Bosch with the system AquaSensor (for example, SMS66GI03E) the pump may be unstable due to contamination of the turbidity sensor. Before diagnosing the pump, check the cleanliness of the sensor!

Once a month|Once every 3 months|Only when the car breaks down|Never cleaned it|Don't know where it is-->

Pay attention to error codes. For example:

• E15 — a problem with the drain (most often a clogged or malfunctioning valve).
• E24 — the pump does not gain the required pressure (may be due to wear on the impeller or a breakdown of the Hall sensor).
• E27 — pump motor overload (requires checking the winding).

Pump diagnostics: step-by-step instructions

Before disassembling the machine, carry out preliminary checks:

Unplug the machine and turn off the water|Make sure the drain hose is not kinked|Check the filter on the bottom of the machine for blockages|Have a bowl ready to catch water during disassembly-->

Next, follow the algorithm:

1. Checking the drain manually

   Open the door, tilt the machine back and see if the water flows out by gravity. If not, there is a blockage in the drain path or the valve is faulty.

2. Impeller test

   Remove the lower basket and filter. Manually rotate the pump impeller (it is located under the filter). If it does not rotate or makes a creaking noise, the problem is in the bearings or foreign objects.

3. Continuity of motor winding

   For this you will need a multimeter. Disconnect the terminals from the pump and measure the resistance between the contacts. Normal value for Bosch — 150–300 Ohm. If the resistance tends to zero, there is a short circuit; if it approaches infinity, there is a break.

   Multimeter mode: Ω (2000 ohms)
   The probes are connected to the pump contacts (usually they are marked L and N).

4. Hall sensor check

   On models with an electronic pump (e.g. Bosch SMV68TX06R) when the impeller rotates, the sensor should produce pulses. They can be checked with an oscilloscope or tester in frequency meter mode.

If after diagnostics it turns out that the pump is faulty, you can try to repair or replace it. In 70% of cases, the breakdown is associated with wear of the impeller or blockage, which can be eliminated without purchasing a new unit.

Typical breakdowns and repair methods

Let's look at the most common pump malfunctions Bosch and options for eliminating them:

Breakdown	Reason	Repair method	Cost (RUB)
The pump does not drain water	Filter or impeller clogged, valve malfunction	Cleaning, replacing the valve (part number 00643754)	300–800
The pump hums, but does not pump	Worn bearings or impeller	Replacing the impeller (part number 00643755) or the entire pump	1 200–2 500
The machine knocks out the machine gun	Short circuit in the winding	Replacing the pump (repairing the winding is not cost-effective)	3 500–6 000
Weak water pressure	Clogged nozzles or worn seals	Cleaning the system, replacing gaskets (set 00643756)	500–1 500

To replace the pump in cars Bosch you will need:

1. Disconnect the machine from the network and water.
2. Remove the bottom panel (in some models, the front panel).
3. Disconnect the drain hose and wires from the pump.
4. Unscrew the mounting screws (usually 2-3 pieces) and remove the pump.
5. Install the new pump in reverse order.

Important: In cars with the system AquaStop (for example, Bosch SMS66GI03E) when replacing the pump, the leakage protection may be triggered. After installing a new node, you must reset the error through the service menu (code for Bosch: press Power + Start and hold for 5 seconds).

How to extend the life of a pump?

Average pump life in Bosch — 5–10 years, but with proper use this period can be extended. Here are some tips:

• 🧼 Use a water softener — hard water accelerates wear of seals and impellers. In cars with WaterSoft (for example, Bosch SMV88TX06R) this is especially critical.
• 🧹 Clean the filter monthly — even small debris damages the pump blades over time.
• 🔌 Connect the car through a stabilizer — voltage surges are detrimental to electronic pumps.
• 🍽️ Don't overload your baskets — excess weight of the dishes increases the load on the pump.
• 🧪 Flush the system with citric acid - once every 3 months, run the machine with 200 g of acid on the program Intensive 70°C.

In machines with function AutoOpen (automatic door opening after washing) the pump experiences additional load due to the frequent activation of the fan. To reduce wear and tear, disable this option in the menu Settings → Drying.

Choosing a new pump: original vs analogues

If repair is not possible, you will have to buy a new pump. Here the question arises: should I buy an original spare part or an analogue? Let's look at the pros and cons of both options:

Criterion	Original pump Bosch	Analogue (for example, Electrolux, Indesit)
Service life	7–10 years	3–5 years
Compatibility	100% suitable for fasteners and connectors	Wiring may require modifications
Price (RUB)	4 000–7 000	1 500–3 000
Warranty	1–2 years	3–6 months
Noise level	Corresponds to the vehicle's passport data	May be 3-5 dB higher

When choosing a pump, pay attention to:

• 🆔 Article - must match the original (for example, 00643754 for Bosch SMS50E22RU).
• 🔌 Connector type — new models use a 4-pin connector, old ones use a 2-pin connector.
• 🔄 Direction of rotation — some analogues rotate in the opposite direction, which leads to errors E24.

Popular analogues for Bosch:

• Electrolux 231666001 - suitable for series SMV/SMS 2015–2020
• Indesit C00284380 — a universal option for machines with a brush motor.
• Samsung DC61-00123B - compatible with Bosch Serie 4, but requires re-soldering of the terminals.

Attention: ⚠️ In cars with the system EcoSilence Drive (brushless pump) installing analogues is highly not recommended - this will lead to errors on the control board.

When should you contact the service?

Not all pump failures can be repaired yourself. Contact the service center if:

• 🔧 Control board needs replacement — the pump may be working properly, but the board does not send signals to it.
• ⚡ Motor winding problem — rewinding is more expensive than a new pump.
• 💻 The machine gives errors E18 or E35 - they are associated with sensors that are calibrated only using diagnostic equipment.
• 🔊 Pump noise is accompanied by vibration of the housing - this may indicate damage to the shaft bearings, which requires complete disassembly of the machine.

Cost of repairing the pump in the service:

• Diagnostics - 800–1,500 rubles.
• Pump replacement - RUB 2,500–4,000. (excluding spare parts).
• System cleaning - 1,000–2,000 rubles.

Official service centers in Moscow and St. Petersburg Bosch They offer a repair guarantee of up to 1 year. However, before your visit, check whether the center works with your model - some services do not accept cars older than 10 years.

FAQ: Frequently asked questions about Bosch pumps

Is it possible to repair a pump if it does not pump water but is humming?

Yes, in most cases the problem can be solved by cleaning the impeller or replacing the O-rings. If the pump hums but does not rotate, check whether a foreign object (for example, a piece of glass) is blocking the impeller. The cause may also be wear of the bearings - in this case, the entire assembly will need to be replaced.

Which pump is suitable for Bosch SMS50E22RU?

The original pump with the article number is suitable for this model 00643754. Among the analogues one can consider Electrolux 231666001 or Indesit C00284380, but some modifications to the fastenings may be required. In cars of 2020 and newer, pumps with a brushless motor are installed - analogues are not suitable for them.

Why does a Bosch machine display error E24 after replacing the pump?

Error E24 indicates a problem with water pressure. After replacing the pump, it can occur for three reasons:

1. Incorrect connection of connectors (check polarity).
2. There is a blockage in the tubes going from the pump to the rocker arms.
3. The need to reset the error through the service menu (press Power + Start, hold for 5 seconds).

If the error remains, the problem may be in the pressure sensor or control board.

How much does a pump cost for Bosch Serie 8?

In series cars Serie 8 (for example, SMV88TX06R) a pump with a brushless motor is used EcoSilence Drive. Its cost is from 5,500 to 7,000 rubles. depending on the supplier. There are no analogues for this model, since the pump is integrated with the system PerfectDry and has a unique connector.

Can a Bosch machine be used without a pump?

No, the pump is a critical element. Without it, the machine will not be able to take in or drain water. If the pump breaks down and repairs are delayed, you can manually fill and drain water, but this risks overflowing and short circuiting. It is better to temporarily switch to hand washing dishes.