The first step is to identify the symptoms reported by the vehicle owner. This may include issues like difficulty starting the engine, dimming headlights, warning lights on the dashboard, or non-functioning electrical accessories.

A visual inspection of the battery, wiring, fuses, and other components is performed to identify obvious issues such as loose connections, damaged wiring, or corroded terminals.

The battery is tested to ensure it has sufficient voltage and amperage. A weak or faulty battery can cause various electrical issues.

The alternator and charging system are tested to ensure they are supplying the right amount of power to recharge the battery and power electrical components.

The starter motor is tested to ensure it is engaging and turning the engine over properly.

OBD scanners can also provide live data, allowing diagnostic scan tools to be connected to the vehicle's onboard diagnostic (OBD-II) system to retrieve trouble codes and additional information about engine and system performance.ng technicians to monitor real-time sensor readings. Freeze frame data, which captures sensor data at the time a DTC is triggered, helps diagnose intermittent issues.

Individual electrical components, such as sensors, ignition system components, relays, and switches, may be tested using specialized tools and procedures.

The wiring harness is inspected for damage, corrosion, or breaks that may be causing electrical issues.

Fuses and relays are checked to ensure they are intact and functioning. Faulty fuses or relays can disrupt electrical circuits.

Voltage drop tests may be conducted to identify high-resistance areas in the electrical system, which can cause issues such as dimming lights or slow cranking.

Once the issue is identified, repairs may involve fixing or replacing faulty components, repairing wiring, or addressing issues with connectors and terminals.

After repairs, the vehicle is reassembled, and comprehensive testing is conducted to ensure that the electrical system functions correctly.