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Interactive diagrams

Click every element to reveal its role, typical value, tests, faults and warnings.

electrical

Basic Electrical Circuit

Battery → fuse → switch → lamp → ground. Click any element to learn its role and how to test it.

9 elements
electrical

Charging Circuit

Alternator, rectifier, regulator, warning lamp and battery. Click parts to understand charging diagnosis.

7 elements
electrical

Battery Internal Construction

Six cells, plates and electrolyte — click to explore what is inside a 12 V battery.

9 elements
fundamentals

Vehicle Energy Flow

From fuel to motion — click each stage to understand the drivetrain.

8 elements
electronics

CAN Bus Topology

Modules share a twisted pair with termination at each end. Click modules and terminations.

7 elements
diagnostics

How a DTC Is Stored

From monitor to warning lamp and repair — click each stage of the diagnostic loop.

6 elements
fundamentals

The Four-Stroke Cycle

Piston, valves, spark plug and crankshaft — the anatomy behind the cycle.

6 elements
electrical

Relay Control Circuit

A small switch current controls a large load current through a relay. Click each part to learn its role and tests.

10 elements
electrical

Starter Motor Circuit

High-current starting circuit: battery, heavy cables, solenoid, motor and engine ground. Click to explore.

7 elements
electrical

Voltage Drop in Series

Unwanted resistance steals voltage from the load. Click the points to see how a voltage-drop test isolates it.

7 elements
engine

Ignition System (Coil-on-Plug)

Battery → fuse → ignition switch → coil → spark plug → engine ground. Click each element.

9 elements
engine

Fuel Injector Circuit

Battery feed through a relay, injector coil, and an ECU ground-side command. Click each element.

7 elements
electronics

Sensor Output Families

Resistive, Hall-effect, inductive and wideband sensors produce different signals. Click each family.

6 elements
engine

Engine Cooling System

Radiator, thermostat, pump, block, fan and expansion tank. Click each element for tests and faults.

8 elements
advanced

Turbocharger System

Exhaust drives the turbine, which drives the compressor; the intercooler cools the charge. Click each part.

8 elements
advanced

EGR System

Recirculated exhaust gas lowers combustion temperature. Click to test the valve and cooler.

6 elements
advanced

Diesel Particulate Filter (DPF)

The DPF traps soot and burns it off during regeneration. Click to explore pressure and temperature sensing.

6 elements
advanced

ABS / ESP System

Wheel speed sensors feed the ABS module, which controls the hydraulic unit. Click each element.

8 elements
advanced

Diesel Common-Rail Fuel System

Fuel path from tank to high-pressure rail and injectors, with a low- and high-pressure side. Click each part.

7 elements
diagnostics

OBD-II Connector (J1962)

The 16-pin diagnostic link connector: power, grounds and the networks behind it. Click each pin group.

6 elements
modern

Hybrid High-Voltage System

Traction battery, service disconnect, inverter, motor and DC/DC — the orange-cable boundary. Awareness only.

6 elements
modern

EV Charging Path

From the charge port through the on-board charger and BMS to the traction battery. Awareness only.

6 elements
electronics

Electronic Throttle Actuator

The ECU drives the throttle motor and reads back two position sensors. Click each element.

7 elements
chassis

Hydraulic Brake Circuit

Pedal, master cylinder, lines, caliper and disc. Click each part to learn its role and tests.

7 elements
chassis

MacPherson Strut Suspension

Spring, damper, top mount, knuckle and control arm. Click each element.

7 elements
transmission

DCT vs CVT Layout

Dual-clutch on the left, continuously-variable principle on the right. Click each part.

7 elements
modern

ADAS Sensor Coverage

Camera, radar, ultrasonic sensors and their coverage. Click each element.

6 elements
modern

48 V Mild-Hybrid System

Belt-starter generator, 48 V battery, DC/DC and the 12 V network. Click each part.

6 elements
climate

AC Refrigeration Circuit

Compressor, condenser, expansion device and evaporator. Click each part to see its role, pressures and tests.

8 elements
tools

Multimeter Controls

Display, function dial and input jacks. Click each part to learn how to set up a digital multimeter safely.

7 elements
tools

Oscilloscope Controls

Screen, channel, time base, voltage scale and trigger. Click each control to learn how to read a signal.

6 elements
electrical

Fuse and Relay Box

A fused supply feeding fuses, a relay and a load. Click each element to learn diagnosis.

6 elements
transmission

Open Differential

Ring gear, pinion, side gears and spider gears. Click each part to understand how torque is split.

6 elements
engine

Oxygen (Lambda) Sensor

Zirconia element, reference air, exhaust gas and signal. Click each part to learn how lambda is measured.

6 elements
modern

EV Battery Pack & BMS

Pack, modules, BMS, contactor and thermal plate. High-voltage awareness only.

8 elements
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