Description of the P0872 fault code.
OBD2 Error Codes

P0872 Transmission fluid pressure sensor/switch ā€œCā€ circuit low.

26.05.2022 /

P0872 ā€“ OBD-II Trouble Code Technical Description

Trouble code P0872 indicates a low signal in the transmission fluid pressure sensor/switch "C" circuit.

What does the fault code mean P0872?

Trouble code P0872 indicates a low signal in the transmission fluid pressure sensor/switch "C" circuit. This means that the automatic transmission control module (TCM) has detected that the signal from the transmission fluid pressure sensor is below the expected level. When this code appears, the Check Engine light will come on. In some cars, the transmission may go into automatic transmission protection mode.

Fault code P0872.

Possible reasons

Some possible reasons for the P0872 trouble code:

  • Faulty transmission fluid pressure sensor: The sensor itself may be damaged or malfunctioning, causing the pressure to be read incorrectly.
  • Problems with wiring or connections: Opens, short circuits or incorrect connections in the electrical circuit can cause a low signal level.
  • Fault inside the gearbox: Problems with the transmission itself, such as clogged or defective hydraulic passages, can cause insufficient transmission fluid pressure.
  • Transmission control module (TCM) problems: A malfunction of the TCM itself, such as a software failure or damage to the control unit, may cause an error in the processing of the pressure signal.
  • Transmission fluid problems: Insufficient or poor quality transmission fluid can also cause low pressure.
  • Problems with the gear shift mechanism: Failure of the gear shift mechanism, including its mechanical or electrical components, can also cause this error.

It is important to conduct a thorough diagnosis to determine the specific cause of the P0872 code in your vehicle.

What are the symptoms of a fault code? P0872?

Symptoms for DTC P0872 may vary depending on specific vehicle conditions and characteristics:

  • The Check Engine light comes on: When trouble code P0872 appears on the vehicle's dashboard, the Check Engine Light (or MIL - Malfunction Indicator Lamp) comes on.
  • Transmission problems: In some cases, the vehicle may exhibit unusual behavior when shifting gears, such as jerking, poor transmission performance, or harsh shifting.
  • Emergency protection mode: In some vehicles with an automatic transmission, when P0872 is detected, the transmission may go into a safety mode, limiting the speed or available gears.
  • Unusual sounds or vibrations: Low pressure in the transmission system may cause unusual sounds or vibrations when the vehicle operates.
  • Loss of productivity: If the vehicle goes into limp mode or performs poorly due to low transmission fluid pressure, it may result in loss of performance and poor driving dynamics.

If you suspect a P0872 code or notice these symptoms, it is recommended that you contact a professional for diagnosis and repair.

How to diagnose a fault code P0872?

The following procedure is recommended to diagnose DTC P0872:

  1. Scan error code: Use a diagnostic scanner to read the P0872 code and any other codes that may be stored in the system.
  2. Checking the transmission fluid level: Check the level and condition of the transmission fluid. Make sure the fluid level is at the recommended level and that the fluid is clean and free of contamination.
  3. Checking the transmission fluid pressure sensor: Check the operation of the transmission fluid pressure sensor to ensure that the pressure is reading correctly. Check electrical connections and wiring for corrosion, breaks or short circuits.
  4. Electrical circuit check: Inspect the electrical circuit, including the wires and connectors associated with the transmission fluid pressure sensor. Make sure all connections are secure and undamaged.
  5. Diagnosis of internal transmission problems: In case all electrical and mechanical components are ok, there may be problems inside the transmission such as clogged hydraulic passages or faulty internal mechanisms. In this case, more detailed diagnostics may be required.
  6. Transmission Control Module Inspection: Check the Transmission Control Module (TCM) for failure or malfunction. The TCM software can also be checked for updates or errors.
  7. Other checks: Check other systems involved in the transmission, such as speed sensors or accelerator pedal position sensors, which may be associated with the P0872 code.

After diagnosing and determining the cause of the error, make the necessary repairs or replace components to resolve the problem. If you are unsure of your skills or experience, it is best to contact a professional mechanic for diagnosis and repair.

Diagnostic errors

When diagnosing DTC P0872, the following errors may occur:

  • Incomplete pressure sensor check: Incomplete or incorrect testing of the transmission fluid pressure sensor may result in undiagnosed problems or erroneous conclusions.
  • Skipping Electrical Circuit Test: Not checking the electrical circuit, including wires, connectors and connections, may result in undetected problems in the electrical system that may be causing the P0872 code.
  • Insufficient check for internal transmission problems: Failure to perform a sufficiently detailed diagnosis of internal transmission problems, such as clogged hydraulic passages or mechanical failure, may lead to incorrect conclusions about the cause of the error.
  • Ignoring other related systems: Skipping tests of other systems, such as speed sensors or accelerator pedal position sensors, that may be related to transmission operation may result in an incomplete diagnosis and incorrect determination of the cause of the P0872 code.
  • Misinterpretation of results: Incorrect interpretation of the data obtained during the diagnostic process can lead to erroneous conclusions about the causes of the P0872 error code and incorrect repairs.

To avoid these errors, it is recommended to conduct a thorough diagnosis, following the vehicle manufacturer's recommendations and using the appropriate tools and techniques.

How serious is the fault code? P0872?

Trouble code P0872 indicates a low signal in the transmission fluid pressure sensor/switch ā€œCā€ circuit. This can have serious consequences for the vehicle's performance and safety. The following are some reasons why a P0872 code should be considered serious:

  • Potential security risk: Low transmission fluid pressure can cause the transmission to perform poorly, which can cause you to lose control of your vehicle while driving, especially on high-traffic roads or expressways.
  • Transmission damage: Low transmission fluid pressure can cause wear or damage to internal transmission components due to inadequate lubrication and cooling. This may require expensive transmission repairs or replacement.
  • Loss of productivity: Low transmission fluid pressure can cause loss of vehicle performance, including poor acceleration, traction and overall driving dynamics.
  • Increased fuel consumption: Improper transmission performance due to low transmission fluid pressure can result in increased fuel consumption due to inefficient gearing and shifting.

In general, trouble code P0872 should be considered serious and requires prompt attention. Diagnosis and repairs must be carried out immediately to prevent possible damage to the vehicle and ensure its safe and reliable operation.

What repair will help eliminate the code? P0872?

Fixing the P0872 trouble code will depend on the specific issue causing the error, but some general steps may help with the repair:

  1. Checking and replacing the transmission fluid pressure sensor: If the pressure sensor is faulty or fails, it must be replaced. This usually involves removing the old sensor and installing the new one, then testing it to see if it works.
  2. Checking and repairing the electrical circuit: Sometimes the cause of the P0872 code can be corrosion or an open circuit in the electrical circuit associated with the pressure sensor. In this case, it is necessary to inspect the electrical wiring and connectors, as well as make the necessary repairs.
  3. Checking and replacing transmission fluid: Low or poor quality transmission fluid can cause P0872. Check the level and quality of the transmission fluid, and replace if necessary.
  4. Gearbox diagnostics and repair: If the problem is not related to the pressure sensor or transmission fluid, there may be problems inside the transmission, such as clogged hydraulic passages or faulty mechanisms. In this case, more detailed diagnostics and possibly repair of the gearbox will be required.
  5. Firmware or replacement of the transmission control module: If the problem is with the Transmission Control Module (TCM), it may require flashing or replacing the module.

These are just general directions of action. Repairs may vary depending on your specific situation and vehicle model. If you do not have the experience or skill to carry out such work, it is recommended that you contact a qualified mechanic for diagnosis and repair.

How to Diagnose and Fix P0872 Engine Code - OBD II Trouble Code Explain

P0872 ā€“ Brand-specific information

Trouble code P0872 can apply to various makes and models of cars, some of them with their meanings:

These are just a few of the possible makes of vehicles that may be affected by DTC P0872. For your specific vehicle make and model, consult a repair manual or consult a professional mechanic.

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