Generac

5-3

UnclassifiedFuel

What This Code Means

Oxygen sensor circuit no activity detected; Electronic Throttle Control Valve (ETC) malfunction

Possible Causes

  • •Faulty oxygen sensor
  • •Wiring integrity issue between the controller
  • •Faulty Electronic Throttle Control Valve (ETC)
  • •Issue with the 4-wire harness connecting the ETC to the ECM
  • •Dedicated ground wire (Wire 820G) issue
  • •Dedicated power supply wire (Wire 820B) issue
  • •Sensor output wire (Wire 766) issue
  • •ETC positive wire (Wire 770) issue
  • •ETC negative wire (Wire 771) issue
  • •ETC motor resistance outside of specification

Suggested Actions

  1. 1Replace oxygen sensor
  2. 2Repair or replace wiring between the controller
  3. 3Troubleshoot Electronic Throttle Control Valve (ETC)
  4. 4Test the 4-wire harness
  5. 5Inspect and test the dedicated ground wire (Wire 820G)
  6. 6Inspect and test the dedicated power supply wire (Wire 820B)
  7. 7Inspect and test the sensor output wire (Wire 766)
  8. 8Inspect and test the ETC positive wire (Wire 770)
  9. 9Inspect and test the ETC negative wire (Wire 771)
  10. 10Measure ETC motor resistance

Related Generac Fault Codes

5-45-53-15-62-626702-526742-426752-32676
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