Transmission Slip Error
Your transmission is slipping, meaning the engine speed increases without matching wheel speed—like spinning your wheels on ice. The ECU detected that the transmission isn't properly locking the engine to the wheels.
The ECU compares input shaft speed (engine) to output shaft speed (wheels) via transmission speed sensors. When the ratio between these speeds exceeds the threshold for the current gear, the ECU logs slip. It monitors torque converter lockup and clutch/band engagement pressure.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Input/Output Speed Ratio | Matches gear ratio within 5% tolerance | Exceeds 8-10% variance, indicating hydraulic or mechanical failure |
| Transmission Fluid Pressure | 200-300 PSI depending on gear | Below 150 PSI or erratic fluctuations |
Code P1733 is a moderate fault. You can generally drive to a workshop, but avoid long trips or high-load driving (motorway, uphill towing) until it is diagnosed. If the code keeps returning after clearing, or if you notice the symptoms listed above worsening, do not delay professional diagnosis. Many moderate codes have multiple possible root causes — a mechanic with live OBD data can identify the exact fault more efficiently than part-by-part trial and error.
Once the fault is repaired, P1733 can be cleared using any OBD-II scanner. Connect the scanner, navigate to "Clear Codes" or "Erase DTCs," and confirm. The check engine light turns off immediately.
The code will return if the root cause was not actually fixed. The ECM re-detects the fault within 1–3 drive cycles and sets the code again.