Wiring fault to the pressure sensor/switch: chafed, open-circuit or short-circuit wires, or a corroded or loose connector; Faulty transmission fluid pressure sensor or switch 'D'; Fluid leaking into the harness or connector, or fluid contaminated with debris or worn clutch material; Low or degraded transmission fluid, or incorrect fluid level; Internal hydraulic fault such as a sticking solenoid, valve body wear or low line pressure that makes the reading implausible; Fault in the transmission control unit or its power and earth supplies; Outdated control unit software where the manufacturer has issued a fix for this code.

P0875

Transmission Fluid Pressure Sensor/Switch D Circuit.

Generic
Powertrain
Generic code
Medium severity

How this code is built

P: SystemPowertrain
0: Defined bySAE, the same on every car
8: AreaTransmission
75: FaultThe specific fault in that area

What it means

P0875 is the generic code for a fault in the Transmission Fluid Pressure Sensor/Switch 'D' circuit. The transmission control unit monitors the signal from this sensor or switch and has seen a voltage or signal that is missing, out of range or does not make sense for the current gear and operating conditions. Which pressure sensor or switch is 'D', and where it sits, depends on the make, model and gearbox.

Symptoms

Gearbox warning light or malfunction indicator lamp on
Harsh, delayed or flared gear changes
Transmission stuck in a fixed gear (limp mode)
Slipping or loss of drive in certain gears
Poor fuel economy or erratic shift points

Possible causes

Wiring fault to the pressure sensor/switch: chafed, open-circuit or short-circuit wires, or a corroded or loose connectorlikely
Faulty transmission fluid pressure sensor or switch 'D'likely
Fluid leaking into the harness or connector, or fluid contaminated with debris or worn clutch materialpossible
Low or degraded transmission fluid, or incorrect fluid levelpossible
Internal hydraulic fault such as a sticking solenoid, valve body wear or low line pressure that makes the reading implausiblepossible
Fault in the transmission control unit or its power and earth suppliesrare
Outdated control unit software where the manufacturer has issued a fix for this coderare

How to diagnose

Read all stored codes and freeze frame data, noting gear, fluid temperature and road speed when the fault set, and check for other transmission codes
Check the transmission fluid level and condition (colour, smell, debris) following the procedure for that model, as some gearboxes need it checked at a set temperature
Visually inspect the sensor, its harness and connector for damage, rubbing, corrosion, fluid ingress and bent or pushed-back pins
Using live data, compare the pressure sensor or switch reading with the expected value in different gear selections, and check whether it changes as it should
Test the circuit's supply voltage, signal and earth at the connector against the manufacturer's data, and check wiring continuity and insulation to the control unit
Wiggle-test the harness with the engine running to see if the signal drops out or the fault returns
Check the control unit's power and earth supplies and look for any software updates or technical bulletins for the model
If the electrical side is sound, carry out a line pressure test and inspect the valve body and solenoids as the manufacturer directs

How to fix

Repair or replace damaged wiring and clean or renew corroded or contaminated connectors
Replace the faulty pressure sensor or switch and its seal
Correct the fluid level, or change the fluid and filter with the specified type if it is degraded or contaminated
Repair or replace the faulty valve body, solenoid or other internal parts if hydraulic pressure is incorrect
Update the control unit software only if the manufacturer lists it as a fix for this fault, or repair or replace the control unit if it is proven faulty

Can I keep driving?

Medium severity

The car may be driveable, but the gearbox could go into limp mode or shift harshly, and continued use with a real pressure problem can cause clutch or internal damage. Have it diagnosed soon, and stop driving if it slips badly or loses drive.

Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.