P0873 Fault Code

Transmission Fluid Pressure Sensor/Switch C Circuit High

• What does that mean?
• Symptoms
• Causes
• Solutions

The P0873 fault code indicates an issue with the Transmission Fluid Pressure Sensor or Switch C, specifically that the circuit is reporting a high voltage. This sensor plays a critical role in monitoring the transmission fluid pressure, helping the vehicle's transmission control module (TCM) regulate shifting and optimize performance.

• The sensor sends pressure information to the TCM.
• High voltage signals can suggest a malfunction, wiring issues, or sensor failure.
• It's essential for maintaining proper transmission function for smooth shifting and efficient operation.

What are the symptoms of the P0873 code?

Common symptoms associated with the P0873 code include:

• Illumination of the Check Engine Light.
• Erratic or harsh shifting of the transmission.
• Reduced acceleration or power.
• Transmission overheating due to improper pressure readings.
• Possible limp mode activation to prevent further damage.

What causes the P0873 code?

Several factors can lead to the P0873 code:

• Faulty Transmission Fluid Pressure Sensor or Switch C.
• Damaged wiring or connectors in the circuit.
• Short circuit within the sensor circuit.
• Low transmission fluid levels or contaminated fluid affecting sensor performance.

How to fix P0873?

To resolve the P0873 fault code, the following steps can be taken:

• Inspect the wiring and connectors associated with the Transmission Fluid Pressure Sensor for damage or corrosion.
• Replace the Transmission Fluid Pressure Sensor if found faulty.
• Check and refill transmission fluid if levels are low.
• Clear the fault codes and test drive the vehicle to ensure that the issue is resolved.