E-Bike Diagnostics and Repair

Lesson 1 • Battery Pack Fundamentals

Explains lithium cell chemistry, pack construction, and battery management system roles. Provides the chemical and electrical context needed for battery diagnostics later.

Lesson 2 • Electrical Safety Principles

Introduces shock hazards, arc flash risks, and safe isolation procedures. Directly enables safe bench work on all subsequent chapters.

Lesson 3 • Control System and Display Overview

Maps the controller, display, and sensor network that govern power delivery. Prepares students to trace signal paths during fault diagnosis.

Lesson 4 • E-Bike Architecture Overview

Covers the major subsystems of a pedal-assist and throttle e-bike. Establishes a shared vocabulary used throughout the entire course.

Lesson 1 • Hand Tools for E-Bike Service

Covers torque wrenches, specialty cassette tools, and motor-specific hardware. Correct tool selection prevents fastener damage and ensures repeatable assembly.

Lesson 2 • Oscilloscope Basics for E-Bikes

Introduces waveform capture for PWM signals, Hall sensor outputs, and CAN bus traffic. Oscilloscope skills extend diagnostic depth beyond static meter readings.

Lesson 3 • Multimeter and Clamp Meter Use

Teaches DC voltage, resistance, continuity, and current measurement on e-bike circuits. Accurate meter use underpins every electrical diagnostic procedure in the course.

Lesson 4 • Workshop Organization and Safety

Establishes bench layout, fire suppression placement, and chemical storage for lithium batteries. A well-organized shop reduces injury risk and improves diagnostic efficiency.

Lesson 1 • BMS Fault Diagnosis

Reads BMS fault codes, tests protection FETs, and verifies communication lines. BMS faults often mimic motor or controller failures, making accurate isolation critical.

Lesson 2 • Safe Pack Disassembly and Reassembly

Guides controlled discharge, housing removal, and cell group handling without shorting. Proper reassembly restores waterproofing and mechanical integrity.

Lesson 3 • Voltage and Cell Balance Testing

Measures pack voltage, individual cell group voltages, and balance deviation under load. Imbalance data drives decisions on BMS replacement or cell-level repair.

Lesson 4 • Capacity and State-of-Health Testing

Uses discharge cycling and capacity analyzers to quantify remaining usable energy. Capacity data provides objective evidence for warranty and replacement recommendations.

Lesson 1 • Mid-Drive Motor Service

Addresses crankshaft interface, torque sensor calibration, and internal gear inspection specific to mid-drive units. Mid-drive service requires drivetrain removal before motor access.

Lesson 2 • Bearing and Seal Replacement

Demonstrates press-fit bearing removal, correct replacement sizing, and seal installation to restore waterproofing. Bearing failure is the most common mechanical motor fault.

Lesson 3 • Motor Performance Verification

Uses software data logging and road simulation to confirm restored torque output and thermal behavior. Verification closes the repair loop before returning the bike to service.

Lesson 4 • Hub Motor Disassembly and Inspection

Covers axle removal, cover separation, and internal inspection of magnets, windings, and bearings. Systematic disassembly prevents magnet and winding damage.

Lesson 1 • Controller Architecture and Signals

Maps MOSFET bridge layout, gate driver signals, and microcontroller I/O pins. Understanding internal architecture guides targeted probing rather than random testing.

Lesson 2 • MOSFET and Output Stage Testing

Uses diode-mode and in-circuit resistance tests to identify shorted or open MOSFETs. Failed output stages cause motor stuttering, overheating, or complete drive loss.

Lesson 3 • Controller Input Fault Diagnosis

Tests throttle, PAS, brake cutoff, and speed sensor inputs for out-of-range or missing signals. Input faults are the most frequent cause of no-assist complaints.

Lesson 4 • Controller Replacement and Configuration

Covers parameter matching, motor pole configuration, and post-replacement functional testing. Incorrect configuration after replacement causes performance loss or component damage.

Lesson 1 • Charging Port and Connector Service

Inspects and replaces damaged charging ports, bent pins, and corroded contacts on the battery housing. Port damage is a leading cause of intermittent charging failures.

Lesson 2 • Smart Charger Communication Faults

Diagnoses handshake failures between smart chargers and BMS communication lines. Communication faults prevent charge initiation even when hardware appears undamaged.

Lesson 3 • Charger Output Testing

Measures no-load and loaded output voltage and current against manufacturer specifications. Out-of-spec chargers cause premature cell degradation or BMS protection trips.

Lesson 4 • Charge Cycle Verification and Documentation

Runs a full charge cycle while logging voltage, current, and temperature to confirm correct operation. Complete documentation supports warranty claims and service records.

Lesson 1 • Suspension Setup for E-Bikes

Adjusts sag, rebound, and compression on forks and rear shocks sized for e-bike weight. Correct suspension setup protects battery mounts and frame welds from fatigue.

Lesson 2 • Drivetrain Wear and Replacement

Measures chain stretch, cassette wear, and chainring condition on mid-drive and hub-drive bikes. Worn drivetrain components accelerate motor wear and reduce range.

Lesson 3 • Wheel Building and Truing for Hub Motors

Addresses spoke tension, dish, and lateral true specific to heavy hub-motor wheels. Improper spoke tension causes spoke fatigue and rim cracking under motor torque.

Lesson 4 • Hydraulic and Mechanical Brake Service

Covers pad replacement, rotor truing, bleed procedures, and brake cutoff sensor alignment. Misaligned cutoff sensors cause persistent motor inhibit faults.

Lesson 1 • Systematic Fault Isolation Methodology

Introduces divide-and-conquer and substitution strategies for multi-system faults. A structured method prevents misdiagnosis and unnecessary part replacement.

Lesson 2 • Intermittent Fault Diagnosis

Uses data logging, thermal cycling, and vibration testing to reproduce and capture intermittent faults. Intermittent faults are the most time-consuming and costly to misdiagnose.

Lesson 3 • CAN Bus and Communication Diagnostics

Captures and decodes CAN bus traffic to identify node dropouts and message errors. Communication faults cause cascading errors across display, controller, and BMS.

Lesson 4 • Complex Case Studies and Repair Planning

Works through multi-fault scenarios combining battery, motor, and controller failures. Case study practice builds diagnostic confidence and efficient repair sequencing.