The P0879 trouble code indicates an intermittent issue with the transmission fluid pressure sensor or switch “D” circuit.
P0879 Transmission Fluid Pressure Sensor/Switch “D” Circuit Intermittent
Code symptoms P0879.
1. Check Engine Light (CEL) may illuminate intermittently.
2. Inconsistent shifting patterns.
3. Harsh or delayed transmission shifts.
4. Reduced fuel efficiency.
5. Transmission overheating in severe cases.
Causes of the code P0879.
1. Loose or corroded wiring connections in the circuit.
2. Faulty transmission fluid pressure sensor or switch “D.”
3. Intermittent short or open circuit in the wiring harness.
4. Problems with the transmission control module (TCM).
Code Solutions P0879.
1. Repair or replace any damaged wiring or connectors in the circuit.
2. Ensure good electrical connections and clean any corrosion from connectors.
3. Replace the transmission fluid pressure sensor or switch “D” if it’s found to be faulty.
4. If intermittent wiring issues are identified, repair or replace the affected wiring harness.
5. Clear the trouble codes from the vehicle’s computer after repairs are complete.
6. Test drive the vehicle to confirm that the issue has been resolved.