Yukon XL 4WD V8-5.3L (2011)
Diagnostic Instructions
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Perform the Diagnostic System Check - Vehicle See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System
Check - Vehicle prior to using this diagnostic procedure.
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Review Strategy Based Diagnosis See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis for an
overview of the diagnostic approach.
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Diagnostic Procedure Instructions See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure Instructions
provides an overview of each diagnostic category.
Diagnostic Fault Information
Circuit/System Description
The data link connector (DLC) is a standardized 16 cavity connector. Connector design and location is dictated by an industry wide standard, and is
required to provide the following:
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Scan tool B+ voltage at terminal 16
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Scan tool ground at terminal 4
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Common ground at terminal 5
Diagnostic Aids
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The scan tool will power up with the ignition OFF. Some modules however, will not communicate unless the ignition is ON and the power mode
master (PMM) module sends the appropriate power mode message.
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If the B+ circuit, ground circuits, and connections of the DLC are functioning properly, the malfunction must be due to the scan tool/CANdi
module.
Reference Information
Schematic Reference
Data Communication Schematics See: Diagrams/Electrical Diagrams
Connector End View Reference
Component Connector End Views See: Diagrams/Connector Views/Connector End Views By Name
Description and Operation
Data Link Communications Description and Operation See: Description and Operation
Electrical Information Reference
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Circuit Testing See: Testing and Inspection/Component Tests and General Diagnostics/Circuit Testing/Circuit Testing
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Connector Repairs See: Testing and Inspection/Component Tests and General Diagnostics/Connector Repairs/Connector Repairs
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Testing for Intermittent Conditions and Poor Connections See: Testing and Inspection/Component Tests and General Diagnostics/Circuit
Testing/Testing for Intermittent Conditions and Poor Connections
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Wiring Repairs See: Testing and Inspection/Component Tests and General Diagnostics/Wiring Repairs/Wiring Repairs
Scan Tool Reference
Control Module References See: Testing and Inspection/Programming and Relearning for scan tool information.
Circuit/System Testing
1. Test for less than 2.0 ohms between the ground circuits terminal 4 of the DLC and ground, and terminal 5 of the DLC and ground.
‹› If greater than the specified range, test the ground circuit for an open/high resistance.
2. Ignition ON, verify a test lamp illuminates between the B+ circuit terminal 16 at the DLC and ground.
‹› If the test lamp does not illuminate, test the voltage supply circuit for a short to ground or an open/high resistance.
