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Home >> Isuzu >> 2004 >> Axiom Base, 4WD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Introduction >> On-Board Diagnostic (OBD-II) >> MIL/RPL Lamp Function Check >> Test Description
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Test Description

Number(s) below refer to the step number(s) on the Diagnostic Chart :

  1. The MIL ("Check Engine lamp") should be "ON" steady with the ignition "ON" and the engine "OFF". If not, the "No MIL" chart should be used to isolate the malfunction.
  2. The RPL ("Reduced Power lamp") should be "ON" (only 3 second) steady with the ignition "ON" and the engine "OFF". If not, the "No RPL "chart should be used to isolate the malfunction.
  3. This test ensures that the ECM is capable of controlling the MIL ("Check Engine lamp") and the MIL ("Check Engine lamp") driver circuit is not shorted to ground.
  4. This test ensures that the ECM is capable of controlling the RPL ("Reduced Power lamp") and the RPL ("Reduced Power lamp") driver circuit is not shorted to ground.
Fig 1: Identifying MIL/RPL Lamp Function Check chart
G02788770Courtesy of ISUZU MOTOR CO.
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