K Yukon/Denali 4WD V8-5.7L VIN R (2000)
An intermittent may be caused by any of the following conditions:
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A poor connection
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Rubbed through wire insulation
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A broken wire inside the insulation
Thoroughly check any circuitry that is suspected of causing the intermittent complaint. Refer to Testing for Intermittent and Poor Connections in
Diagrams. If a repair is necessary, then refer to Wiring Repairs or Connector Repairs in Diagrams.
TEST DESCRIPTION
The numbers below refer to the step numbers in the diagnostic table.
1. This step determines if the scan tool powers up when connected to the DLC.
2. The MIL should be ON when the ignition is turned ON.
4. Refer to DTC List (DTC Type Table Domestic) for a list of valid DTCs. See: Computers and Control Systems/Testing and Inspection/Diagnostic
Trouble Code Descriptions
5. Refer to Data Link Connector (DLC) Schematics in Data Link Connectors to determine all of the modules communicating on the Class 2 Serial
Data circuit. If any of the modules are not present in the Diagnostic Circuit Check, then the modules never established communications. The scan
tool will indicate a YES state for communicating modules and a NO state for modules that had established, yet no longer communicate.
7. If the vehicle does not start or starts and stalls, the Passlock system could be the cause.
8. This test determines if the MIL can be controlled by the VCM.
9. Comparing the ACTUAL and TYPICAL scan tool data values will aid in determining whether an engine parameter is within limits (i.e., Advanced
timing can substantially alter sensor values.)
