Definition
A fault code identifies a specific malfunction a device's self-diagnostics have detected and confirmed: a function has already been affected, unlike an alarm that may only warn of an approaching condition. Fault codes are typically numbered per manufacturer and product family and map to a documented cause in the OEM manual.
Key facts
- Identifies a confirmed malfunction, not just a threshold warning: the affected function has already been disrupted.
- Numbering and meaning are manufacturer- and product-specific; the same number differs across families (e.g., Siemens F30001 vs. F07801).
- Usually requires acknowledgement or a reset sequence, and may block restart until cleared.
- Distinct from a diagnostic code, which is the broader class of technical identifiers a system can produce beyond faults.
What information does Fault code preserve?
A fault code is generated when a device's internal diagnostics detect and confirm a malfunction: an electrical, mechanical, or logical condition that has already disrupted a monitored function, not merely approached a limit.
How do maintenance teams use Fault code?
An alarm code can appear before any function is actually disrupted, flagging a condition worth attention. A diagnostic code is the umbrella term covering status, event, warning, and fault codes together. A fault code is the specific subset confirming an actual malfunction, which is why manufacturer fault-code tables (as documented for specific device and firmware versions) are the authoritative source for what a given number means.
FAQ
Frequently asked questions
Which detected malfunction does a fault code identify?
It identifies a specific malfunction a device's diagnostics have confirmed has already affected a function, as opposed to an alarm that can appear before any function is disrupted.
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