FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Description of On-Board Diagnostics

Diagnosis of vehicle systems other than the body system uses the DRB to read hard trouble code messages. The reason for the trouble code is then diagnosed to find the source of the problem.

The DRB is used to read body system trouble codes also. However, not all body system problems have a corresponding trouble code. In some cases, when a body system does not operate properly, a warning code will appear or the customer will describe a complaint.