Danger: This procedure should not be performed on high voltage circuits. Performing this procedure on high voltage circuits may result in serious injury or death.
Caution: Refer to Test Probe Caution in the Preface section.
The following procedures test for a short to ground in a circuit.
With a DMM
- Remove the power feed (i.e. fuse, control module) from the suspect circuit.
- Disconnect the load.
- Set the rotary dial of the DMM to the ohm position.
- Connect one lead of the DMM to one end of the circuit to be tested.
- Connect the other lead of the DMM to a good ground.
- If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp
- Remove the power feed (i.e. fuse, control module) from the suspect circuit.
- Disconnect the load.
- Connect one lead of the test lamp to battery positive voltage.
- Connect the other lead of the test lamp to one end of the circuit to be tested.
- If the test lamp illuminates, there is a short to ground in the circuit.
Fuse Powering Several Loads
- Review the system schematic and locate the fuse that is open.
- Open the first connector or switch leading from the fuse to each load.
- Connect a DMM across the fuse terminals (be sure that the fuse is powered).
• | When the DMM displays voltage the short is in the wiring leading to the first connector or switch. |
• | If the DMM does not display voltage refer to the next step. |
- Close each connector or switch until the DMM displays voltage in order to find which circuit is shorted.