Fault Codes/Cummins/2398Cummins2398UnclassifiedCoolingWhat This Code MeansWarning lamp active; Displayed message: AMBIENT TEMPERATURE OORPossible Causes•Ambient temperature sensor is out of range (OOR), high or lowRelated Cummins Fault Codes2416C10002263C11001667C12501435C13001433C14001335C1500Browse all Cummins fault codes→ASK RUDY ABOUT THIS FAULTGet a diagnosis walkthrough for 2398 on your specific Cummins unit — cited to the OEM manual, not a forum guess.Your question about 2398GET THE ANSWERFree account required — we'll bring your question with you.