Fault Codes/Power Solutions International/1603Power Solutions International1603UnclassifiedGeneralWhat This Code MeansVRelay <%VBat specified in the calibrationPossible Causes•DTC 685 or 6987 set•Faulty power relay fuse•Loss of battery voltage to and from the power relaySuggested Actions1Check power relay fuse. Repair as needed.2Perform On-Board (OBD) System Check3Check for battery voltage to and from the power relay. Repair as needed.4Refer to diagnostics for the set fault (DTC 685 or 6987). Repair and retest.Related Power Solutions International Fault Codes16121613160216141352-1360161516161351162511731627Browse all Power Solutions International fault codes→ASK RUDY ABOUT THIS FAULTGet a diagnosis walkthrough for 1603 on your specific Power Solutions International unit — cited to the OEM manual, not a forum guess.TRY IT FREE