K 2500 Truck 4WD V8-379 6.2L DSL VIN C FI (1989)
Voltage Drop Test
TESTING FOR VOLTAGE DROP
This test checks for voltage being lost along a wire, or through a connection or switch.
1. Connect the positive lead of a voltmeter to the end of the wire (or to one side of the connection or switch) which is closer to the Battery.
2. Connect the negative lead to the other end of the wire (or the other side of the connection or switch).
3. Operate the circuit.
4. The voltmeter will show the difference in voltage between the two points.
Testing for Short with Test Light or Voltmeter
TESTING FOR SHORT TO GROUND
With a Test Light or Voltmeter
1. Remove the blown fuse and disconnect the load.
2. Connect a test light or voltmeter across the fuse terminals (be sure that the fuse is powered).
3. Beginning near the Fuse Block, wiggle the harness from side to side. Continue this at convenient points (about 6 inches apart) while watching
the test light or voltmeter.
4. When the test light glows, or the voltmeter registers, there is a short to ground in the wiring near that point.