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Home >> Cadillac >> 2007 >> Escalade EXT >> Repair and Diagnosis >> External Pages >> Different car >> Section 351 (Cellular Communication System) >> Diagnostic Information and Procedures >> OnStar Call Center Remote Function Requests Inoperative >> Diagnostic Aids
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Diagnostic Aids

WARNING: This page is about a different car, the 2004 GMC Sierra, 2004 GMC Cab & Chassis Sierra, 2004 Chevrolet Silverado, and 2004 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

The customer concern may have been due to a lack of cellular service in a given area or a failure in the National Cellular Network infrastructure that has since been corrected.

OnStar Call Center Remote Function Requests Inoperative

Step Action Yes No
Schematic Reference: OnStar Schematics 
Connector End View Reference: Cellular Communication Connector End Views 
1 Did you perform the Cellular Communication Diagnostic System Check? Go to Step 2  Go to Diagnostic System Check - Cellular Communication 
2 Attempt to honk the horn, operate the lights and lock or unlock the doors on the vehicle.
Does the applicable system operate properly?
Go to Step 3  Go to
3
IMPORTANT: It is necessary to inform the OnStar® Call Center advisor that this call is for vehicle diagnostic purposes.
  1. Contact the OnStar® Call Center by pressing the blue OnStar® button.
  2. Ask the OnStar® advisor to perform a remote function (door lock/unlock, light flash, or horn honk).
Was the attempt successful?
Go to Diagnostic Aids Use the scan tool to access the STID and ESN and contact the General Motors Technical Assistance Center