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HOMESERVICE MANUALSCHEVROLET2008CHEVY EXPRESS G2500, VAN CARGO, 6.6 6REPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 1005 (DATA COMMUNICATION SYSTEM)DIAGNOSTIC INFORMATION AND PROCEDURESSCAN TOOL DOES NOT COMMUNICATE WITH HIGH SPEED GMLAN DEVICEDIAGNOSTIC FAULT INFORMATION
2008 Chevrolet Chevy Express G2500, Van Cargo, 6.6 6

Diagnostic Fault Information

2008 Chevrolet Chevy Express G2500, Van Cargo, 6.6 6SECTION Diagnostic Fault Information
WARNING: This page is about a different car, the 2007 GMC Sierra and 2007 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
Scan Tool Does Not Communicate with High Speed GMLAN Device

Circuit Short to Ground Open/High Resistance Short to Voltage Signal Performance
High Speed GMLAN Serial Data Bus (+) 1 21 1 -
High Speed GMLAN Serial Data Bus (-) 1 21 1 -
Ground (DLC, Terminal 5) - 1 - -
1 An open between the data link connector (DLC) and the first splice will only effect the communication with the scan tool. The vehicle modules will still communicate.
  1. No communication on any high speed GMLAN module
  2. An open in only one high speed GMLAN serial data circuit may allow degraded communication between the modules.
RENDER: 1.0x

NO RELATED

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