Do all Shimano STEPS bikes have brake sensors?

Most STEPS bikes from E6100 generation onwards include brake sensors as standard. Some earlier E5000 installations and some budget configurations may omit them. If your bike has no brake sensor cables connected to the motor, you do not have brake sensors and they cannot be causing your fault.

Shimano STEPS Brake Sensor Error Fix

Shimano STEPS Brake Sensors

Shimano STEPS uses magnetic brake sensors built into the brake levers to detect when brakes are applied and immediately cut motor output. This is a safety feature — it prevents the motor from fighting the brakes. The sensors are simple two-wire magnetic reed switches that connect to the motor controller via small diameter cables.

Brake sensor faults are a frequently overlooked cause of Shimano STEPS errors. A permanently triggered brake sensor (stuck in "brakes applied" state) produces constant motor cutout that riders often mistake for a motor or battery fault. A completely failed sensor or its cable can produce E020 communication errors.

Symptoms of Brake Sensor Fault

Motor cuts out randomly mid-ride — The sensor is intermittently triggering as if the brake is applied.
Motor does not engage at all — The sensor is permanently triggered in "brakes applied" state.
E020 communication error — A failed sensor cable is producing bus interference.
Reduced assistance in one specific brake position — The sensor triggers when the handlebar is in a certain position, indicating cable routing is at fault.

Fix Procedure

Step 1: Isolate the Faulty Sensor

Disconnect the brake sensor cables from the motor one at a time and test if the fault clears. If disconnecting the front brake sensor resolves the issue, that sensor or its cable has failed. Reconnect the good sensor before riding.

Step 2: Check Sensor Magnet Position

The Shimano brake lever sensor is a reed switch that activates when a magnet on the brake lever moves into proximity. Look for the small square magnet on the brake lever body. If it has shifted or is missing, the sensor is permanently activated. Reposition the magnet to the marked position on the lever.

Step 3: Inspect Sensor Cable

Trace the sensor cable from the lever to the motor. Look for pinching under bar clamps or handlebar tape, and for tight bends. A crushed cable causes intermittent sensor activation — the symptom appears when the bar is turned to a specific angle.

Step 4: Replace the Sensor

Shimano STEPS brake sensors are inexpensive and rider-replaceable. The sensor clips into the brake lever body without tools in most designs. Route the new cable alongside the brake hose and secure with small cable ties at 10 cm intervals.

Shimano STEPS Brake Sensor Fault: Diagnosis & Fix