OBD Code P0730

Incorrect Gear Ratio

What’s mean?

OBD2 Code P0730 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 speed sensor (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 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 P0730
– Engine Light ON (or Service Engine Soon Warning Light) – Incorrect transmission shifting

Possible Causes

Possible causes of P0730
– Low transmission fluid level – Dirty transmission fluid – Shift solenoids – Shift solenoids harness or connectors – Transmission mechanical problems – Transmission hydraulic control circuit The Error code is generally activated on detection of the following conditions: The TCM has detected that the transmission is trying to mechanically shift to a lower gear than intended

Possible Solutions