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Home >> Cadillac >> 2012 >> Escalade EXT >> Repair and Diagnosis >> External Pages >> Different car >> Section 637 (Keyless Entry System) >> Diagnostic Information and Procedures >> Diagnostic System Check - Remote Keyless Entry >> Test Description
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Test Description

WARNING: This page is about a different car, the 2003 GMC Sierra, 2003 GMC Cab & Chassis Sierra, 2003 Chevrolet Silverado, and 2003 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

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

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.

5. 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. Any other body control module DTCs displayed by the scan tool do not apply to Remote Keyless Entry and should be diagnosed in the applicable section.

Fig 1: Diagnostic System Check - Remote Keyless Entry
G01577450Courtesy of GENERAL MOTORS CORP.