DTC P0603: ECM/PCM Internal Control Module Keep Alive Memory (KAM) Error Turn the ignition switch ON (II). Clear the DTC with the HDS. Wait 1 second. Check for Temporary DTCs or DTCs in the DTCs MENU with the HDS. Is DTC P0603 indicated?
YES | - | Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM, then recheck. If the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM /PCM.■
NO | - | Intermittent failure, system is OK at this time.■