E-bike diagnostic checklist for shops

Intake5

• Record make, model, drive system, battery capacity and frame serial
• Record battery serial and drive unit serial where readable
• Customer complaint in their words: when it happens, how often, in which assist mode
• Odometer reading and total hours from the display or diagnostic tool
• Any recent crash, water exposure, wash with a pressure washer, or other shop work

Battery5

• Inspect the case for cracks, swelling, impact damage and heat marks; quarantine any damaged battery
• Read state of health, capacity and charge cycles with the system maker diagnostic tool
• Check the battery locks into the mount firmly and the lock and key work
• Check charge level indicator matches what the display reports
• Note the rider charging and storage habits

Charger4

• Confirm the charger is the correct model for the battery
• Inspect cable, plug and case for damage, cuts and heat marks
• Check the charger indicator lights through a charge cycle
• Measure output voltage with a multimeter against the rating on the label, where safe and appropriate

Contacts and connectors5

• Battery contacts on battery and mount: corrosion, pitting, burn marks, bent pins, debris
• Clean contacts with a suitable contact cleaner; do not file them
• Motor, display, remote, sensor and light connectors: fully seated, pins straight, no water or corrosion
• Cable routing: no pinching at the headset, BB area or dropouts, no chafe through the insulation
• Charging port cover present and closing

Drive unit5

• Drive unit mounting bolts tight to the frame maker torque
• Listen under load and freewheeling: grinding, knocking, clicking, whine
• Check for crank play at the drive unit, separate from the crank arm bolts
• Hub motor: axle nuts or thru-axle tight, torque arms fitted, cable exit not strained
• Check for water ingress signs around the housing and cable entries

Sensors5

• Torque sensor: assist responds smoothly to pedal pressure; follow the maker calibration or start-up procedure (some systems need no pressure on the pedals at power-on)
• Cadence sensor: assist starts and stops with pedaling
• Speed sensor: magnet present, secure and aligned with the sensor, gap within the maker spec
• Check the displayed speed against a known reference on a test ride
• Check the wheel circumference setting matches the fitted tire

Display, controls and software5

• Display powers on, backlight and buttons work, remote responds
• Read and record every stored error code with the maker diagnostic tool
• Look up each code in the maker documentation; do not guess
• Check installed firmware against the current release; update with the maker tool if the customer approves
• Clear codes only after the fault is fixed and recorded

Lights, brakes and wear6

• Integrated lights on, beams aimed, rear light working
• Brakes rated by their maker for e-bike use; rotors and pads suited to the bike weight and speed
• Pad and rotor wear: e-bikes wear both faster; check against the minimums
• Tires rated for e-bike use where the maker specifies; check pressure and wear
• Chain and cassette wear; e-bike chains stretch faster under motor torque
• Test ride in every assist mode: assist cut-in, cut-out at the legal speed limit, walk mode