The following sequence of events should occur when diagnostics are functioning normally:
• With the ignition switch in the "on" position, the check engine fight should be on steady.
• When the T circuit is grounded, the check engine light should flash a normal code if all monitored circuits are in proper working order.
• If a fault exists in any monitored circuit, the appropriate diagnostic code should be displayed. If there is more than one code stored in the ECU keep alive memory, codes will be displayed in numerical sequence from lowest to highest.
• Diagnostic codes will continue to repeat until the key is turned off or the T circuit ground is removed.
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