OBD-II Trouble Code Description for P0731 Ford

Gear 1 Incorrect Ratio

What does this mean?

OBD2 Code P0731 Ford definition:
This diagnosis monitors actual gear position by checking the torque converter slip ratio calculated by Transmission Control Module (TCM) as follows: Torque converter slip ratio = A x C/B A: Output shaft revolution signal from revolution sensor B: Engine speed signal from Engine Control Module (ECM) C: Gear ratio determined as gear position which TCM supposes If the actual gear position is higher than the position (1st) supposed by TCM, the slip ratio will be more than normal. In case the ratio exceeds the specified value, TCM judges this diagnosis malfunction.

Symptoms

Possible sumptoms of OBD code P0731 Ford
– Engine Light ON (or Service Engine Soon Warning Light) – Incorrect transmission shifting

Causes

Possible causes of OBD code P0731 Ford
– Low transmission fluid level – Dirty transmission fluid – Shift solenoids – Transmission mechanical problems – Transmission hydraulic control circuit The Error code is generally activated on detection of the following conditions: P0731 Ford is detected when A/T cannot be shifted to the 1st gear position even if electrical circuit is good.

Possible Solutions