DTC P0601: Internal Control Module Memory Check Sum Error Or
WARNING: This page is about a different car, the 1997 Suzuki Swift. However, it is still accessible from the selected car via links, so may be relevant.
Connect scan tool to Data Link Connector (DLC). Clear DTCs. Turn ignition off. Start engine if possible. If DTC P0601 or P0603 resets, replace PCM. Retest system.