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Testing For Short to Ground

Testing For Short With Self Powered Test Light Or Ohmmeter:




WITH A TEST LIGHT OR DIGITAL VOLTMETER (DVM)
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 DVM.
4. When the test light glows, or the DVM registers, there is a short to ground in the wiring near that point.

Testing For Short With Test Light Or DVM:




WITH A SELF-POWERED TEST LIGHT OR OHMMETER.
1. Remove the blown fuse and disconnect the Battery and load.
2. Connect one lead of a self-powered test light or ohmmeter to the fuse terminal on the load side.
3. Connect the other lead to a known good ground.
4. Beginning near the Fuse Block, wiggle the harness from side to side. Continue this at convenient points (about 6 inches apart) while watching the self-powered test light or ohmmeter.
5. When the self-powered test light glows, or the ohmmeter registers, there is a short to ground in the wiring near that point.

FUSES POWERING SEVERAL LOADS
1. Find the schematic under "Fuse Block Details," for the fuse that has blown.
2. Open the first connector or switch leading from the fuse to each load.
3. Replace the fuse.
^ If the fuse blows, the short is in the wiring leading to the first connector or switch. Use a test light or meter as described.
^ If fuse does not blow, refer to next step.
4. Close each connector or switch until the fuse blows in order to find which circuit has the short. Connect test lamp or meter at the connector to the suspect circuit (disconnected) rather than at the fuse terminals.