P0733 indicates that the Powertrain Control Module has detected that the actual gear ratio in third gear does not match the expected ratio. This usually points to a problem with the transmission’s internal components or the sensors that monitor gear position.
Internal wear or failure of the clutch pack that provides the third‑gear ratio can cause the actual ratio to drift outside specifications.
A solenoid that controls hydraulic pressure for third gear may be stuck, leaking, or not receiving proper command signals.
The transmission input or output speed sensor may be providing inaccurate pulses, leading the PCM to calculate an incorrect gear ratio.
Insufficient or degraded fluid can affect hydraulic pressure and clutch engagement, resulting in an incorrect gear ratio.
Only after ruling out mechanical and sensor problems should the PCM be considered; a software update or rare internal failure may be the cause.
It is possible but uncommon. The PCM is usually correct; most P0733 codes are caused by mechanical wear, solenoid issues, or sensor problems. Replace or reprogram the PCM only after all other possibilities have been ruled out.
Clearing the code may turn off the warning light temporarily, but if the underlying issue (e.g., worn clutch pack or bad sensor) remains, the code will return.
The vehicle can usually be driven, but performance may be degraded, and further transmission damage could occur if the problem is not addressed promptly.
Not necessarily. Many P0733 diagnoses result in a solenoid replacement, sensor repair, or fluid service. Only if internal clutch components are worn will a major repair or rebuild be required.