Shimano Steps Error W013: Torque Sensor Initialization Incomplete — 3-Step Fix & Part Fitment
Cause: Drive unit torque strain gauge could not calibrate zero-offset during startup because rider foot pressure was resting on the pedal. Ride Status: REDUCED ASSIST — Clears Automatically After Correct Reboot. Signal Pattern: Warning W013 on SC-E7000 / E8000 / EP8 Display. Most riders resolve W013 in 1–5 min using the 3-step diagnostic checklist below (starting with the free mechanical/connector reset before ordering a €0 replacement sensor).
Interactive 3-Step Workshop Repair Checklist (Check as You Test)
Shimano Steps motors (E6100, E7000, E8000, EP8, EP801) zero their internal strain-gauge torque sensor in the first 3 seconds after pressing Power. If your foot is resting on a pedal—or the bike is leaning with a pedal pressed against a curb—W013 triggers. Turn off, remove all weight from pedals, and power on.
If W013 appears even with feet off the pedals, check that the rear derailleur clutch or a seized chain link isn't pulling tension on the front chainring at rest. Shift to a middle cog and spin the cranks backward half a turn before booting.
Connect via Bluetooth to the Shimano E-TUBE Project Cyclist app -> Maintenance -> Error Log / Sensor Calibration, with the bike upright and unloaded.
Model Variant Pinout & Part Compatibility Matrix
| Model / Generation | OEM Part / Ref | Connector / Harness Type | Workshop Installation Note |
|---|---|---|---|
| Shimano EP8 / EP801 / E8000 eMTB | DU-EP800 | Internal Strain Gauge Torque Sensor | Never press the power button while pedaling or rolling. |
| Shimano Steps E6100 / E5000 City & Trekking | DU-E6100 | Internal Torque + Coaster/Nexus Hub | With internal gear hubs, release back-pedal coaster tension before turning on. |