GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2009 🢒 SLS 🢒 Diagnostic Navigation 🢒 Vehicle Diagnostic Information 🢒 Testing for Short to Ground

Caution: Do not insert test equipment probes (DMM etc.) into any connector or fuse block terminal. The diameter of the test probes will deform most terminals. A deformed terminal will cause a poor connection, which will result in a system failure. Always use the J-35616 GM-Approved Terminal Test Kit in order to front probe terminals. Do not use paper clips or other substitutes to probe terminals.

When using the J-35616 GM-Approved Terminal Test Kit, ensure the terminal test adapter choice is the correct size for the connector terminal. Do not visually choose the terminal test adapter because some connector terminal cavities may appear larger than the actual terminal in the cavity. Using a larger terminal test adapter will damage the terminal. Refer to the J-35616 GM-Approved Terminal Test Kit label on the inside of the J-35616 GM-Approved Terminal Test Kit for the correct adapter along with the connector end view for terminal size.

The following procedures test for a short to ground in a circuit.

Using a DMM
  1. Remove the power feed (i.e. fuse, control module) from the suspect circuit.
  2. Disconnect the load.
  3. Set the rotary dial of the DMM to the W position.
  4. Connect one lead of the DMM to one end of the circuit to be tested.
  5. Connect the other lead of the DMM to a good ground.
  6. If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.

Using a Test Lamp
  1. Remove the power feed (i.e. fuse, control module) from the suspect circuit.
  2. Disconnect the load.
  3. Connect one lead of the test lamp to battery positive voltage.
  4. Connect the other lead of the test lamp to one end of the circuit to be tested.
  5. If the test lamp illuminates, there is a short to ground in the circuit.

When Power is Supplied by the Fuse to Multiple Loads
  1. Review the system schematic and locate the fuse that is open.
  2. Open the first connector or switch leading from the fuse to each load.
  3. Connect a DMM across the fuse terminals (be sure that the fuse is powered).
    4. • 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.
  4. Close each connector or switch until the DMM displays voltage in order to find which circuit is shorted.