Hombre S Space Cab 2WD V6-4.3L (2000)
With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
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 one end of the circuit to be tested.
4. Connect the other lead of the test lamp to battery positive voltage.
5. Connect the other end of the circuit to ground.
6. If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Short to Ground
NOTE: Refer to Test Probe Note in Cautions and Notes.
The following procedures test for a short to ground in a circuit
With 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 ohm 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.
With 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.
Fuse Powering Several 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).
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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.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is shorted.
Testing For A Short to Voltage
NOTE: Refer to Test Probe Note in Cautions and Notes.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position.
2. Connect the positive lead of the DMM to one end of the circuit to be tested.
3. Connect the negative lead of the DMM to a good ground.
4. Turn ON the ignition and operate all accessories.
5. If the voltage measured is greater than 1 volt, there is a short to voltage in the circuit.
General Electrical Diagnosis Procedures
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures contained in this section. You should understand the basic
theory of electricity and know the meaning of voltage (volts), current (amps) and resistance (ohms). You should understand what happens in a circuit
with an open or a shorted wire. You should be able to read and understand a wiring diagram. Refer to Strategy Based Diagnosis in General Information
in order to properly diagnose and repair the customer concern.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness if the malfunction appears to be vibration related.
Manipulation of a circuit can consist of a wide variety of actions, including:
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Wiggling the harness
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Disconnecting a connector and reconnecting
