Avalanche 1500 2WD V8-5.3L VIN T (2002)
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 1 lead of the test lamp to 1 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 Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at convenient points (about 6 inches apart) while watching
the test equipment.
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Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing For Short to Ground
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Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for Continuity
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Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM. This feature allows you to manipulate the circuit
without having to watch the DMM. The DMM will generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J 39200 can monitor current, resistance or voltage
while recording the minimum (MIN), and maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See: General Electrical Diagnostic
Procedures/Troubleshooting Tools/Troubleshooting With A Digital Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position.
3. Press the range button of the DMM in order to select the desired voltage range.
4. Press the MIN MAX button of the DMM. The DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has been recorded.
7. Press the MIN MAX button once in order to display the MAX value and note the value.
8. Press the MIN MAX button again in order to display the MIN value and note the value.
9. Determine the difference between the MIN and MAX values.
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If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an intermittent open or high resistance condition exists.
Repair the condition as necessary.
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If the variation between the recorded MIN and MAX voltage values is less than 1 volt an intermittent open or high resistance condition does
not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the following items:
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Wiring broken inside the insulation
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Poor connection between the male and female terminal at a connector-Refer to Testing for Proper Terminal Contact for the specific procedure.
See: General Electrical Diagnostic Procedures/Circuit Testing/Testing For Proper Terminal Contact
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Poor terminal to wire connection-Some conditions which fall under this description are poor crimps, poor solder joints, crimping over the wire
insulation rather than the wire itself and corrosion in the wire to terminal contact area, etc.
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Wire insulation which is rubbed through- This causes an intermittent short as the bare area touches other wiring or parts of the vehicle.
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Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in order to verify the complaint. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
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Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high resistance, short to ground, and short to voltage
conditions. See: Diagrams/Diagnostic Aids
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Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General Electrical Diagnostic Procedures/Circuit Testing/Scan
Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
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J 42675 flatware Probe Adapter
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J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before replacing a suspect component. Mating terminals must be
