Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer is having trouble reading the pressure of the transmission fluid. It's like trying to listen to a radio station that keeps cutting in and out.
The transmission fluid pressure sensor/switch D sends signals to the vehicle's computer about the pressure inside the transmission. An intermittent issue suggests that the signal is not consistent.
The P0879 code is triggered when the Powertrain Control Module (PCM) detects an intermittent signal from the transmission fluid pressure sensor/switch D. This sensor monitors the hydraulic pressure in the transmission, which is crucial for proper gear shifting.
• Check Engine Light is on
• Erratic or harsh shifting
• Transmission slipping
• Faulty transmission fluid pressure sensor/switch
• Damaged or corroded wiring or connectors
• Low transmission fluid levels
PCM: Powertrain Control Module, the vehicle's computer that controls the engine and transmission.
OBD-II: On-Board Diagnostics, a standardized system for self-diagnostics in vehicles.
• Use an OBD-II scanner to confirm the code.
• Inspect the transmission fluid level and condition.
• Check the wiring and connectors for damage or corrosion.
• Replace the faulty transmission fluid pressure sensor/switch.
• Repair or replace damaged wiring or connectors.
• Refill or replace transmission fluid as necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly check and maintain transmission fluid levels.
• Inspect wiring and connectors for wear or damage.
• Schedule routine transmission maintenance.
Sensor Issue
• Avoid driving the vehicle until the issue is resolved to prevent further damage.
• Consult with a professional mechanic for a proper diagnosis.
Check your vehicle's warranty coverage for transmission components.
The P0879 code has been associated with intermittent transmission issues in various vehicle models, often due to sensor or wiring problems.
Moderate – Addressing this issue promptly can prevent further transmission damage.
Driving with a faulty transmission sensor can lead to unsafe driving conditions. It is advised to resolve the issue as soon as possible.
• Vehicle must be running.
• Transmission fluid must be at operating temperature.
The transmission fluid pressure sensor is typically located on the transmission housing.
Q: Can I drive with a P0879 code?
A: It's not recommended to drive with this code as it can lead to transmission damage.
Q: How do I reset the P0879 code?
A: After repairs, use an OBD-II scanner to clear the code. If the issue persists, further diagnosis is needed.
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