Also called: brake sensors, e-brake switches, cut-off switches
What it does
They stop the motor fighting the brakes. Many e-bikes have them, especially hub-motor bikes with throttles.
Signs of a problem
- Motor won't help at all, but the display is fine
- Assist cuts in and out
Safe things to check
- Squeeze and release each brake lever firmly; a lever that doesn't fully spring back keeps the motor off.
- Check nothing is pressing on a lever, like a bag strap.
Looking after it
- If a lever is bent or sticky, have it fixed; brakes come first.