Fault Codes/Power Solutions International/DTC 51Power Solutions InternationalDTC 51UnclassifiedGeneralWhat This Code MeansMalfunction Indicator Light (MIL) ON during active faultPossible Causes•Bad heater element in the HEGO sensor•Break in the wire harness on the heater supply or control circuits•Fault within the ECMRelated Power Solutions International Fault CodesDTC 52DTC 102 9DTC 15 74DTC 121DTC 2 99DTC 123DTC 2 34DTC 127DTC -1644DTC 1298920DTC 148Browse all Power Solutions International fault codes→ASK RUDY ABOUT THIS FAULTGet a diagnosis walkthrough for DTC 51 on your specific Power Solutions International unit — cited to the OEM manual, not a forum guess.TRY IT FREE