Fault Codes/Rehlko/0X0001Rehlko0X0001UnclassifiedGeneralWhat This Code MeansModbus Register 40001 content changes to 0x0001Possible Causes•Modbus module loses communication with the deviceRelated Rehlko Fault Codes12263535A3638394040A414861Browse all Rehlko fault codes→ASK RUDY ABOUT THIS FAULTGet a diagnosis walkthrough for 0X0001 on your specific Rehlko unit — cited to the OEM manual, not a forum guess.Your question about 0X0001GET THE ANSWERFree account required — we'll bring your question with you.