Jumper wires allow a circuit to by-pass a suspected opening or break in a circuit. Use a jumper wire
to check for open relay contacts, wire breaks and poor ground connections. Several jumper wires with different tips should be available.
If the circuit works correctly with the jumper wire in place, but does not work when the jumper wire is
removed, the circuit is open.
A circuit with no openings or breaks has continuity (uninterrupted current flow) and needs no further
testing.
An opening in the ground circuit exists for the following:
• A switch is closed but the light does not illuminate.
• Jumping the switch does not illuminate the light.
• Jumping the light to the ground causes the light to illuminate.
