Diagnostic Link 6.4 Main Menu This page will be your source for the latest file and information updates to your Detroit Diesel Diagnostic Link 6.X software. New Software Update Information This latest version of DDDL 6.45 software is required to support VCU software 14.26.  Please review the Readme file for updated information. DDDL 6.45 Readme. Documentation Detroit Diesel Diagnostic Link User Guide DDEC Reports 6.45 MBE Electronic Controls Features: Cruise Control PasSmart Engine Protection Progressive Shift Fuel Economy Incentive (FEI)