The control module detected that the measured gear ratio did not match the commanded gear (Gear 1). This is the manufacturer-specific definition used by Ford.
TuningBot DTC Database · v4.37.15
P1721 Ford - Gear 1 Incorrect Ratio
Manufacturer-specific interpretation for Ford. All interpretations of P1721
What P1721 means
Related and nearby codes
How to read P1721
Powertrain: engine, transmission and driveline systems.
Manufacturer-defined range: the meaning can differ between brands.
Specific fault index within the subsystem.
Frequently asked questions about P1721
What does P1721 mean?
Gear 1 Incorrect Ratio. The control module detected that the measured gear ratio did not match the commanded gear (Gear 1). This is the manufacturer-specific definition used by Ford.
Is P1721 generic or manufacturer-specific?
P1721 is a manufacturer-specific code. In this database it is documented for: Ford. The same number can mean something different on other brands.
Can TuningBot remove P1721 at file level?
If the fault logic lives in the ECU calibration, yes: our DTC Removal file service disables the specific fault entry. Checksum correction is not included: it is a separate, optional service. Not sure whether your case qualifies? Request a free assessment and our engineers will check your ECU file.
Other file services
Understand the system behind this code: Diagnostic Strategy and DTC Logic
