Working on the Electrical System

A test light or a digital multimeter can be very helpful for testing circuits. Tools and Equipment for more information on test equipment.

Current flow is logical, always moving from the highest potential at the voltage source (+) toward the lowest potential at ground (-). Using a wiring diagram to trace a circuit, you should start with the ground and then follow the wires back to the source of power.

To troubleshoot a circuit:
1. Inspect all connections, especially grounds. Make sure they are clean, tight and corrosion-free.
2. Check the fuses.


NOTE: Repeated fuse failures are the sign of a faulty wire, a failed component, or a short to ground somewhere in the circuit.

3. Check for voltage reaching particular components or points in the circuit.
4. Check continuity between points to look for breaks in the circuit (open circuit).
5. Check voltage drop at connections, especially ground connections.