Fault Codes/Rehlko/516600 3Rehlko516600 3UnclassifiedGeneralWhat This Code MeansSCR system (Secondary 1 DCU Sensor supply) - Critical over-voltageRelated Rehlko Fault Codes516600 4516663 0516284 17516663 31516281 15516666 163516667 3162A-22760061ACCY PWROVER WARNINGBrowse all Rehlko fault codes→ASK RUDY ABOUT THIS FAULTGet a diagnosis walkthrough for 516600 3 on your specific Rehlko unit — cited to the OEM manual, not a forum guess.Your question about 516600 3GET THE ANSWERFree account required — we'll bring your question with you.