P0993
Transmission Fluid Pressure Sensor/Switch "F" Circuit Range/Performance
- Severity
- High
- Driving
- Drive only to a garage
Transmission fluid pressure sensor or switch "F" is answering, but the pressure it reports does not match what the module expects for the gear it commanded. Either the sensor is inaccurate or the pressure genuinely is wrong - and the second is the more serious, because low pressure means clutches are slipping.
Possible causes
- CommonGenuinely low line pressure - low fluid, blocked filter, worn pump
- CommonFailing or drifting pressure sensor
- CommonSticking valve in the valve body
- CommonWorn clutch pack leaking pressure past its seals
- PossibleFailed pressure control solenoid
- PossibleDebris partially blocking the passage to the sensor
What you might notice
- Slipping under load
- Harsh, delayed or flaring shifts
- Limp mode
- Burnt smell from the fluid
- Check engine light on
What to check, in order
- Check the fluid level and condition first, and look for clutch material in it.
- Establish whether the transmission is actually slipping. If it is, the sensor is probably telling the truth.
- A line pressure test with a gauge separates a lying sensor from real low pressure, and is worth paying for before buying parts.
- Check the filter if it has never been changed.
- Do not keep driving a transmission that is slipping - clutches destroy themselves quickly once they start.
Read this code from your own car
Plug an ELM327 adapter into the OBD-II port under the dashboard. Pin16 reads every stored, pending and permanent code, explains each one like this page does — offline, with no account — and shows what the car recorded when the fault was set.
Where this code sits
P00xxP01xxP02xxP03xxP04xxP05xxP06xxP07xxP08xxP09xxP0AxxP0BxxP0CxxP0DxxP0ExxP0FxxP10xxP11xxP12xxP13xxP14xxP15xxP16xxP17xxP18xxP19xxP1AxxP1BxxP1CxxP1DxxP1ExxP1FxxP20xxP21xxP22xxP23xxP24xxP25xxP26xxP27xxP28xxP29xxP2AxxP2BxxP2CxxP2DxxP2ExxP2FxxP30xxP31xxP32xxP33xxP34xxP35xxP36xxP37xxP38xxP39xxP3AxxP3BxxP3CxxP3DxxP3ExxP3Fxx
Transmission and control modules
P0900P0901P0902P0903P0904P0905P0906P0907P0908P0909P0910P0911P0912P0913P0914P0915P0916P0917P0918P0919P0920P0921P0922P0923P0924P0925P0926P0927P0928P0929P0930P0931P0932P0933P0934P0935P0936P0937P0938P0939P0940P0941P0942P0943P0944P0945P0946P0947P0948P0949P0950P0951P0952P0953P0954P0955P0956P0957P0958P0959P0960P0961P0962P0963P0964P0965P0966P0967P0968P0969P0970P0971P0972P0973P0974P0975P0976P0977P0978P0979P0980P0981P0982P0983P0984P0985P0986P0987P0988P0989P0990P0991P0992P0993P0994P0995P0996P0997P0998P0999