On-Board Diagnostic System: Overview

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The speed control and charging systems are monitored by the engine controller. The engine controller monitors critical input and output circuits within these systems, making sure they are operating correctly.

Some circuits are tested continuously; others are checked only under certain circumstances.

Each circuit monitored by the engine controller has a corresponding fault message assigned to it. Refer to "System Fault Messages" later in this section for a list and definition of the fault messages.

- If the on-board diagnostic system senses that one of the circuits is malfunctioning, it stores the corresponding fault message in memory.
- If the malfunction goes away after the fault is stored, the fault message will be erased after 50 key cycles.
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