FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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DTC 53: Diagnostic Monitor Internal Fault

Normal Operation
The diagnostic monitor performs several on-board diagnostics every time the ignition switch is turned on. It any of these tests fail, the diagnostic monitor will flash Diagnostic Trouble Code 53.

Possible Causes
Internal diagnostic monitor on-board diagnostic failure.

Pinpoint Test Steps:

53-1 - 53-2: