Bosch Washer Error Code E28 — What It Means & How to Fix It

What Does This Error Mean?

The E28 error on your Bosch washer means the motor speed sensor (also called the tachometer or tacho) is not sending a proper signal. The control board uses this sensor to monitor drum rotation speed. If the signal is absent or irregular, the machine stops the cycle to prevent damage.

Affected Models

Bosch 300 Series
Bosch 500 Series
Bosch 800 Series
Most Bosch front-load washers

Common Causes

The motor tacho (speed sensor) coil has failed and is not generating a signal
The wiring between the motor and control board is damaged or has come loose
The drive belt has broken or slipped off — the motor spins but the drum does not
A heavy or unbalanced load has caused the motor to stall repeatedly
The motor itself has failed or developed a winding fault

How to Fix It

Stop the cycle and unplug the washer. Open the door and redistribute the laundry evenly in the drum.

A heavily unbalanced load can stall the motor. Redistributing clothes is always the first step.
Plug the washer back in and try a spin-only cycle with a smaller, balanced load.

If the spin works with less laundry, you were consistently overloading the machine.
Listen for the drum turning during the wash phase. If the motor runs but the drum does not spin, the drive belt may be broken or slipped.

A broken belt requires accessing the back of the machine to inspect and replace.
Check the wiring harness connections between the motor and control board. Reseat any connectors that have come loose.

Vibration during spin cycles can work connectors loose over time.
If all checks pass but the error persists, the motor tacho (speed sensor) or motor itself likely needs replacement by a technician.

The tacho is a small coil attached to the motor — it can often be replaced without replacing the whole motor.

When to Call a Professional

If redistributing the load and resetting the machine does not clear E28, a technician should inspect the drive belt and motor tacho. Motor tacho replacement costs roughly $80–$180. A failed motor is a larger repair that may cost $250–$450 or more.

Frequently Asked Questions

What is a motor tacho on a washing machine?

The tacho (short for tachometer) is a small sensor attached to the motor. It generates a small electrical signal that pulses in time with the motor's rotation. The control board counts these pulses to know exactly how fast the drum is spinning. If the tacho fails, the board loses visibility into drum speed and stops the cycle.

Can a broken drive belt cause E28?

Yes. If the belt breaks, the motor runs but the drum stands still. The tacho on the motor still signals the board, but other sensors may detect no drum movement. On some Bosch models, this specific mismatch triggers E28.

How much does it cost to replace a Bosch washer motor tacho?

The tacho part typically costs $20–$50. But accessing it requires partially disassembling the washer. Labor adds $60–$130, bringing the total to roughly $80–$180 at most appliance repair shops.