FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Hard Codes

HARD CODES
Any Diagnostic Trouble Code (DTC) that is set whenever the system or component is monitored is a HARD code. This means that the problem is there every time the TCM checks that system or component. Some codes will set immediately at start up and others will require a road test under specific conditions. It must be determined if a code is repeatable (Hard) or intermittent before attempting diagnosis.