Loader finds these problems FAST: High Corrosive Resistance Shorts to Ground Open Circuits Loader Test Leads load the circuit to see if current can flow. By loading the circuit Loader makes a voltage drop test on the fly . Just press the switch – the test results can not lie. Use Loader w/your DMM and follow our test method - you will find wiring faults quicker. Loader Test Leads feature Steady Pin Probe Tips which allows the probe to sit firmly on a male ECM or connector pin. Loader are OEM approved – finds corroded circuits fast!