Curriculum
Module 03foundation
Fuses, Relays, Switches & Electronic Load Control
Understand how power is protected and switched, from conventional relays to ECU transistor and smart power-distribution outputs.
Lessons
10
Estimated time
200 min
Completed
00/10
By the end of this module
Understand exactly how a load is protected, switched and controlled — then test the control path.
Lessons
10 total
- 01Circuit Protection FundamentalsSelect and test protection devices and distinguish cause from consequence.20 min
- 02Testing Fuses ProperlyTest fuses efficiently without relying on appearance.20 min
- 03Conventional Automotive RelaysRead and test standard relay circuits confidently.20 min
- 04Relay Control DiagnosisDetermine why a relay is not energising or not delivering load power.20 min
- 05Mechanical Switches and Position InputsTest simple switches and understand how ECUs interpret their state.20 min
- 06High-Side and Low-Side DriversRecognise electronically switched circuits and test them without expecting a conventional relay.20 min
- 07PWM Load ControlRecognise PWM control and know when a scope or duty-cycle function is more informative than DC voltage.20 min
- 08Smart Fuse Boxes and Power Distribution ModulesDiagnose a load that is controlled electronically rather than by a replaceable relay.20 min
- 09Short-Circuit Diagnosis Without Repeatedly Blowing FusesSystematically locate a short without repeatedly sacrificing fuses or damaging wiring.20 min
- 10Diagnostic Case: Inoperative High-Current LoadUse circuit architecture to isolate whether the failure is protection, control, wiring or the load itself.20 min