Fault Codes/Rehlko/EXTERNAL BATTERY LOWRehlkoEXTERNAL BATTERY LOWUnclassifiedElectricalWhat This Code MeansExternal Battery Low messagePossible Causes•Low generator set engine starting battery•Low generator set engine starting battery voltageSuggested Actions1Check battery connections and voltageRelated Rehlko Fault CodesEXTERNALBATTERYLOWF1EMERG PWR ONF2CURRENT A HIGHF2 (5A-T)CONNOTDETERMF3CONCHECKFAILF4CHECK AC SENS LOSSFAIL TO ACQUIREBrowse all Rehlko fault codes→ASK RUDY ABOUT THIS FAULTGet a diagnosis walkthrough for EXTERNAL BATTERY LOW on your specific Rehlko unit — cited to the OEM manual, not a forum guess.Your question about EXTERNAL BATTERY LOWGET THE ANSWERFree account required — we'll bring your question with you.