Fault Codes/Discovery Energy, LLC (Rehlko)/3217 31Discovery Energy, LLC (Rehlko)3217 31UnclassifiedSensorsWhat This Code MeansHEGO sensor No Activity Detected (B1S1)Possible Causes•Problem with the HEGO sensor or leadsSuggested Actions1Troubleshoot the HEGO sensor for bad leads2Refer to the Heated Exhaust Gas Oxygen Sensor (HEGO) sectionRelated Discovery Energy, LLC (Rehlko) Fault CodesP26 - 47P26 - 48P0133P0134P1135P1136P1138 3217 31P2195P2196P2231P2270P2271Browse all Discovery Energy, LLC (Rehlko) fault codes→ASK RUDY ABOUT THIS FAULTGet a diagnosis walkthrough for 3217 31 on your specific Discovery Energy, LLC (Rehlko) unit — cited to the OEM manual, not a forum guess.Your question about 3217 31GET THE ANSWERFree account required — we'll bring your question with you.