FMI 13 — Out of calibration
The device works but its learned zero or span is off. Very common after a repair when the reset step got skipped.
Common causes
- Calibration/learn procedure not performed after replacement
- Drifted sensor
- Mechanical stop or linkage changed position
- Wrong part number installed
What to test, in order
- Run the manufacturer's calibration or learn routine
- Verify part number against the ESN build list
- Compare the sensor's key-off value with ambient reference
- Inspect for a moved bracket, stop or linkage
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