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Home >> Isuzu >> 2003 >> Axiom Base, RWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> System Tests >> No Reduced Power Lamp >> Test Description
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Test Description

  1. 2

    A NO RPL condition accompanied by a no-start condition suggests a faulty PCM ignition feed or battery feed circuit.
  2. 9

    Using a test light connected to battery positive, probe each of the Multiplex Control Unit ground terminals to ensure that a good ground is present. Refer to Multiplex Control Unit Terminal End View for terminal locations of the Unit Terminal End View for terminal locations of the Multiplex Control Unit ground circuits.
  3. 12

    Using a test light connected to battery positive, probe each of the PCM ground terminals to ensure that a good ground is present. Refer to PCM Terminal End View for terminal locations of the PCM ground circuits.
  4. 21

    In this step, temporarily substitute a known good relay for the PCM relay. The horn relay is nearby, and it can be verified as good simply by honking the horn. Replace the horn relay after completing this step.
  5. 24

    This vehicle is equipped with a PCM which utilizes an Electrically Erasable Programmable Read Only Memory (EEPROM). When the PCM is replaced, the new PCM must be programmed.