What does code P1721 mean?

Q: What does code P1721 mean?

Gear 1 Incorrect Ratio. P1721 on Ford vehicles means the transmission control module (TCM) has calculated that the actual gear ratio in first gear does not match the ratio it expects for that gear. The TCM monitors input shaft speed versus output shaft speed and flags the code when the calculated ratio falls outside the programmed tolerance for first gear.

DTC codes / Ford codes / P1721

P1721 · FordGear 1 Incorrect Ratio

P1721 on Ford vehicles means the transmission control module (TCM) has calculated that the actual gear ratio in first gear does not match the ratio it expects for that gear. The TCM monitors input shaft speed versus output shaft speed and flags the code when the calculated ratio falls outside the programmed tolerance for first gear.

SystemPowertrain

Code typeFord specific

SeverityHigh

Fix difficultyProfessional

AreaTransmission

Guidance is general and written for Ford vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.