44
Blower calibration fault
This code typically points to
- Calculated blower speed below 250 RPM or above 1300 RPM
- Blower wheel drag/restriction
- ECM module or tach/rpm feedback issue
- High static causing blower control problems
Next checks to confirm
- Verify blower wheel spins freely and airflow path is not excessively restricted
- Inspect ECM wiring/module and blower RPM feedback
- Follow OEM blower calibration/ECM diagnostic procedure
Escalation
If code 41 is also present, focus on blower communication/module failure.
Reset behavior
Sequence-dependent; heating mode defaults and fallback behavior depend on operating mode.
Urgent
Fix now