Fault Codes/Rehlko/REPLACE CLOCK BATTERYRehlkoREPLACE CLOCK BATTERYUnclassifiedElectricalWhat This Code MeansAlarm 'Replace Clock Battery' appears on the controllerPossible Causes•CR1220 internal battery power is low•Real Time Clock (RTC) battery power is lowSuggested Actions1Have an authorized Kohler service representative service the controllerRelated Rehlko Fault CodesRY CRLO WARNING WSREAL POWER LOWUFREAL POWER HIGHUL 94 HF1REACTIVE POWER LOWUNDERFREQUENCYOVERTEMP FAULTUNDERSPEEDOUUNDERVOLTAGEBrowse all Rehlko fault codes→ASK RUDY ABOUT THIS FAULTGet a diagnosis walkthrough for REPLACE CLOCK BATTERY on your specific Rehlko unit — cited to the OEM manual, not a forum guess.TRY IT FREE