Vehicle Electrical System Troubleshooting

The video tutorial addresses a client's complaint about multiple electrical issues in a car, including non-functioning indicators, defroster, and ventilation. The instructor uses a diagnostic approach, starting with initial tests and hypotheses about common electrical sources like fuses and relays. Through systematic testing and analysis, the instructor identifies a faulty relay as the root cause. The video concludes with a demonstration of replacing the relay, restoring the car's functions, and explaining the relay's operation.

What were the initial symptoms observed in the vehicle?

• The radio was malfunctioning.

• The indicators, defroster, and ventilation were not working.

• The headlights were flickering.

• The engine wouldn't start.

What was the first hypothesis for the common point of failure?

• A faulty ignition switch.

• A broken wire in the dashboard.

• A malfunctioning battery.

• A common electrical supply issue.

Why was the hypothesis of a common ground point dismissed?

• Because the vehicle had multiple ground points.

• Because the battery was new.

• Because the lights were working.

• Because the fuses were intact.

Where did the technician decide to start the inspection?

• The fuse panel inside the vehicle.

• The dashboard.

• The engine compartment.

• The battery terminals.

What was discovered about the fuses during the inspection?

• No fuses were receiving power.

• The fuses were incorrectly installed.

• All fuses were blown.

• The fuses were missing.

What was the next component suspected after the fuse inspection?

• The ignition switch.

• The relay.

• The battery.

• The alternator.

What is the function of a relay in an electrical system?

• To store electrical energy.

• To convert AC to DC.

• To control high power circuits with a low power signal.

• To measure electrical resistance.

How many terminals does a typical relay have?

• 5 or 6

• 4 or 5

• 3 or 4

• 2 or 3

What was the final test to confirm the relay was faulty?

• Inspecting for physical damage.

• Swapping it with a known good relay.

• Measuring the voltage drop.

• Checking for continuity.

What was the outcome after replacing the faulty relay?

• All previously malfunctioning components started working.

• Only the indicators started working.

• The vehicle wouldn't start.

• The vehicle still had issues.