P0995

What it means

P0995 is the generic code for a high input on the transmission fluid pressure sensor or switch 'F' circuit. The transmission control module saw a voltage or signal on that circuit above the expected range, or a reading that did not match the commanded hydraulic state. Which pressure sensor or switch is 'F', and where it sits in the gearbox, depends on the make, model and transmission.

Symptoms

• Gearbox warning light or engine management light on
• Transmission stuck in a fixed gear (limp mode)
• Harsh, delayed or flared gear changes
• Erratic shift timing or unexpected gear hunting
• Reduced performance or loss of manual shift mode
• Torque converter lock-up not engaging

Possible causes

• Wiring fault on the sensor circuit, such as a short to voltage or a chafed or damaged harnesslikely
• Corroded, loose or contaminated connector at the sensor or transmission control modulelikely
• Faulty fluid pressure sensor or switch 'F' giving a high or stuck signallikely
• Incorrect, degraded or contaminated transmission fluid, or a wrong fluid level affecting pressure readingspossible
• Hydraulic fault such as a sticking valve in the valve body causing a genuine pressure mismatchpossible
• Internal harness fault inside the transmission, or a faulty mechatronic or valve body unit on integrated designspossible
• Faulty transmission control module or outdated softwarerare

How to diagnose

1. Read all stored and pending codes plus freeze frame data, and note whether other transmission pressure or solenoid codes are present.
2. Check the transmission fluid level and condition against the manufacturer's procedure, looking for burnt smell, debris or the wrong fluid type.
3. Inspect the wiring and connectors from the sensor to the control module for chafing, heat damage, water ingress, corrosion and bent or pushed-back pins.
4. Using the model's wiring diagram, identify sensor 'F' and check the reference voltage, signal and earth at the connector.
5. Watch the live pressure sensor or switch reading with the engine running and through gear selections, comparing it with the expected values for that transmission.
6. Test the sensor circuit for short to voltage and for resistance and continuity end to end.
7. Check for technical service bulletins and software updates relevant to the model and transmission.
8. If the electrical side is sound, carry out pressure testing or inspect the valve body as the manufacturer specifies.

How to fix

• Repair or replace damaged wiring and renew any corroded or damaged connectors.
• Replace the faulty pressure sensor or switch 'F' once the circuit has been proven good.
• Correct the fluid level, or replace the fluid and filter with the specified type if it is degraded or contaminated.
• Repair or replace the valve body or mechatronic unit if a hydraulic or internal electrical fault is confirmed.
• Update the transmission control module software if an outdated calibration is a known cause, or replace the module if proven faulty.

Can I keep driving?

Nearby codes

• P0994GenericTransmission Fluid Pressure Sensor/Switch F Circuit Low
• P0996GenericTransmission Fluid Pressure Sensor/Switch F Circuit Intermittent