Possible causes – Faulty Transaxle Control Module(TCM) or Engine Control Module(ECM)– Transaxle Control Module(TCM) to Engine Control Module(ECM) harness is open or shorted– Transaxle Control Module(TCM) to Engine Control Module(ECM) circuit poor electrical connection Symptoms – Engine Light ON (or Service Engine Soon Warning Light) P1603 KIA OBD Code Description A communication line exists between…