Testing for Short to Ground
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Testing for Short to Ground
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Refer to
Test Probe Caution
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The following procedures test for a short to ground in a circuit.
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With a Digital Multimeter (DMM)
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1.
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Remove the power feed (i.e. fuse, control module) from the suspect circuit.
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3.
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Set the rotary dial of the DMM to the Ω position.
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4.
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Connect one lead of the DMM to one end of the circuit to be tested.
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5.
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Connect the other lead of the DMM to a good ground.
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6.
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If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
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1.
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Remove the power feed (i.e. fuse, control module) from the suspect circuit.
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3.
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Connect one lead of the test lamp to battery positive voltage.
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4.
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Connect the other lead of the test lamp to one end of the circuit to be tested.
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5.
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If the test lamp illuminates, there is a short to ground in the circuit.
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Fuse Powering Several Loads
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1.
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Review the system schematic and locate the fuse that is open.
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2.
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Open the first connector or switch leading from the fuse to each load.
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3.
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Connect a DMM across the fuse terminals (be sure that the fuse is powered).
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When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
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If the DMM does not display voltage refer to the next step.
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4.
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Close each connector or switch until the DMM displays voltage in order to find which circuit is shorted.
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