When is a default value used by a controller?

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Multiple Choice

When is a default value used by a controller?

Default values are used as a safe fallback by a controller whenever sensor input can’t be trusted. The controller continually checks sensor data for plausibility and consistency. If a sensor’s data is invalid, missing, or suspected of being false, the system substitutes a predefined, conservative value so operation remains stable and safe instead of acting on faulty information. This predefined value is stored in the software and kept within safe limits, and normal control resumes once valid data returns. Sometimes using a default can also trigger a fault indication or limp mode to alert the system/subsystem owner that there’s a sensor issue. These defaults aren’t about being in park, low battery, or only at startup; they’re used whenever sensor data is unreliable or out of range to maintain safe behavior.

Default values are used as a safe fallback by a controller whenever sensor input can’t be trusted. The controller continually checks sensor data for plausibility and consistency. If a sensor’s data is invalid, missing, or suspected of being false, the system substitutes a predefined, conservative value so operation remains stable and safe instead of acting on faulty information. This predefined value is stored in the software and kept within safe limits, and normal control resumes once valid data returns. Sometimes using a default can also trigger a fault indication or limp mode to alert the system/subsystem owner that there’s a sensor issue.

These defaults aren’t about being in park, low battery, or only at startup; they’re used whenever sensor data is unreliable or out of range to maintain safe behavior.

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