Cause
Hydraulic system leak
A leak in the circuit operating an automated clutch or gearbox. The pump runs more and more often to hold pressure, which is both the early warning and what eventually destroys a pump sized for intermittent duty — so acting on the cycling before the pump fails is the difference between a seal and a unit.
Typically specialist work. Needs equipment or training most home workshops do not have.
Some of these codes mean you should stop driving
2 of the 12 codes this can cause indicate a fault where continuing to drive risks damage or is unsafe. Which one you have matters more than the cause does — read the code's own page before deciding.
Codes this can cause (12)
Codes where this is a likely explanation first, rather than merely a possible one.
- P0933 Hydraulic Pressure Sensor Range/Performance Likely for this code High
- P0942 Hydraulic Pressure Unit Likely for this code High
- P0943 Hydraulic Pressure Unit Cycling Period Too Short Likely for this code High
- P0944 Hydraulic Pressure Unit Loss of Pressure Likely for this code Stop driving High
- P0946 Hydraulic Pump Relay/Control Circuit Range/Performance Likely for this code High
- P2712 Hydraulic Power Unit Leakage Likely for this code Stop driving High
- P0934 Hydraulic Pressure Sensor Circuit Low High
- P0936 Hydraulic Pressure Sensor Circuit Intermittent High
- P0938 Hydraulic Oil Temperature Sensor Range/Performance Moderate
- P277A Electric/Auxiliary Transmission Fluid Pump B Hydraulic Leakage Moderate
- P27E1 Electric/Auxiliary Transmission Fluid Pump A Pressure Too Low Moderate
- P27E2 Electric/Auxiliary Transmission Fluid Pump B Pressure Too Low Moderate
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
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