Hombre S Space Cab 2WD V6-4.3L (2000)
Backprobe
Do not disconnect the connector and probe the terminals from the harness side (back) of the connector.
IMPORTANT:
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Backprobe connector terminals only when specifically required in diagnostic procedures.
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Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack connector, a Micro-Pack connector, or a flat wire
(dock and lock) connector.
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Backprobing can be a source of damage to connector terminals. Use care in order to avoid deforming the terminal, either by forcing the test probe
too far into the cavity or by using too large of a test probe.
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After backprobing any connector, inspect for terminal damage. If terminal damage is suspected, test for proper terminal contact.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Note in Cautions and Notes.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only be tested with a 10 megaohm or higher
impedance digital multimeter such as the J39200.
The J39200 Instruction Manual is a good source of information and should be read thoroughly upon receipt of the DMM as well as kept on hand for
future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits. While a test lamp shows whether voltage is present,
a DMM indicates how much voltage is present.
The ohmmeter function on a DMM shows how much resistance exists between two points along a circuit. Low resistance in a circuit means good
continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with a DMM. This prevents incorrect readings. DMMs
apply such a small voltage to measure resistance that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find out if a component is affecting a measurement take a
reading once, then reverse the leads and take a second reading. If the readings differ the solid state component is affecting the measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
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Backprobe both ends of the connector and either hold the leads in place while manipulating the connector or tape the leads to the harness for
continuous monitoring while you perform other operations or test driving. Refer to Probing Electrical Connectors.
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Disconnect the harness at both ends of the suspected circuit where it connects either to a component or to other harnesses.
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If the system that is being diagnosed has a specified pinout or breakout box, it may be used in order to simplify connecting the DMM to the circuit
or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
NOTE: Refer to Test Probe Note in Cautions and Notes.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J34142-B Test Lamp is Micro-Pack compatible and comprised of a 12 volt light bulb with an attached pair of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground.
2. Touch the other lead to various points along the circuit where voltage should be present.
3. When the bulb illuminates, there is voltage at the point being tested.
Using Fused Jumper Wires
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J36169-A fused jumper includes small clamp connectors that provide adaptation to most connectors without damage. This fused jumper wire is
supplied with a 20 A fuse which may not be suitable for some circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being
tested.
Measuring Voltage
NOTE: Refer to Test Probe Note in Cautions and Notes.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary.
2. Enable the circuit and/or system being tested. Use the following methods:
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Turn ON the ignition, with the engine OFF.
