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Home >> GMC >> 2002 >> Jimmy 2D Utility, Part Time, Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 825 (Lighting Systems) >> Diagnostic Information and Procedures >> DTC B2620: I/P Dimmer Switch Circuit >> 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. 3.  Tests for the proper operation of the circuit in the low voltage range.
  2. 4.  Tests for the proper operation of the circuit in the high voltage range. If the fuse in the jumper opens when you perform this test, the signal circuit is shorted to ground.
  3. 5.  Tests for a short to voltage in the 5 volt reference circuit.
  4. 6.  Tests for a high resistance or an open in the dimming return circuit.
Fig 1: DTC B2620 Diagnostic Procedure (Step 1 To 8)
G01457458Courtesy of GENERAL MOTORS CORP.
Fig 2: DTC B2620 Diagnostic Procedure (Step 9 To 16)
G01457459Courtesy of GENERAL MOTORS CORP.
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