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Home >> Pontiac >> 2001 >> Aztek Base, AWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 640 (Lighting Systems) >> Diagnostic Information & Procedures >> Diagnostic System Check - Lighting Systems >> Test Description
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Test Description

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The number(s) below refer to the step number(s) on the diagnostic table.

  1. 2.  Lack of communication may be due to a partial malfunction of the class 2 serial data circuit or due to a total malfunction of the class 2 serial data circuit. The specified procedure will determine the particular condition.
  2. 3.  Checks for BCM DTCs.
  3. 4.  The presence of DTCs which begin with "U" indicate some other module is not communicating. The specified procedure will compile all the available information before tests are performed.
Fig 1: Diagnostic System Check - Lighting Systems
G01696597Courtesy of GENERAL MOTORS CORP.