DTC Diagnostic Strategy
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If the module DTC list results in a large number of DTCs, diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011, and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern DTCs are present, diagnose those after any module hard faults and before any network faults.
Diagnose all current and active DTCs before diagnosing any historic DTCs.