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Home >> Cadillac >> 2012 >> Escalade EXT >> Repair and Diagnosis >> External Pages >> Different car >> Section 243 (Cellular Communication System) >> Diagnostic Information and Procedures >> Diagnostic System Check - Cellular Communication >> Test Description
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Test Description

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The numbers below Refer to the step numbers on the diagnostic table.

  1. 2.  Lack of communication may be due to a partial malfunction or a total malfunction of the class 2 serial data circuit. The specified procedure will determine the condition.
  2. 5.  The presence of DTCs which begin with "U" indicate some other system control module is not communicating.
Fig 1: Diagnostic System Check - Cellular Communication
G02422499Courtesy of GENERAL MOTORS CORP.