Operation CHARM: Car repair manuals for everyone.

Diagnostic Aids

Circuit Testing:





Using an LED Test Light or Voltmeter (Multimeter)

1 - Remove the fuse
2 - Disconnect the load (powered components) to eliminate the circuit's normal path to ground (GND)


Voltage: If the test light or multimeter indicates Voltage, then there is a complete circuit - a connection to ground (GND) even though all the circuit's Normal ground (GND) paths are eliminated. There is a short - an unintentional connection to ground (GND) somewhere in the circuit.

NO Voltage: There is not a complete circuit. The circuit's normal ground (GND) paths have been disconnected, and there is no other connection between the isolated circuit and ground (GND) - no short has been detected.

CAUTION: Direct contact with meter probes at the connector terminals can easily damage the small contacts, causing poor connections and risking future intermittent malfunctions.