Diagnosis & Repair Procedure
WARNING: This page is about a different car, the 2003 Suzuki Aerio. However, it is still accessible from the selected car via links, so may be relevant.
Substitute ECM with a known good unit and repeat DTC CONFIRMATION TEST . If DTC P0601 does not reset, problem is intermittent. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES article.