P2D8FEngine Oil Pressure Sensor/Switch C Circuit Low
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- P2D8F means the signal of oil pressure sensor C lies below its valid electrical range, which usually points to a short to ground, a lost supply or a defective sensor. Audi uses the code on 2025–2026 A5, S5, Q5 and SQ5 models with the 2.0 TFSI EA888 evo5 (TSB 2079097): engine control unit J623 stores it with symptom 17004, and the cluster may show the oil pressure and emission warnings. The first release blamed the control unit calibration. The revision adds that a voltage spike from a powerful charger switched on together with the ignition can set it, so the charger is connected first, the memory cleared and no parts replaced unless the code comes back. For sensor A, Ford flags an analog signal under 0.25 V for 5 s and a GM 2024 engine table under 0.25 V for 1 s. High is P2D90.
- What you may notice
- Oil pressure warning without real pressure loss
- Emission control warning lamp
- Warning message in the instrument cluster
- Likely causes
- LikelySignal or supply wire of sensor C shorted to ground
- PossibleVoltage spike from a workshop charger switched on with the ignition (Audi EA888 evo5)
- PossibleSensor C defective with output stuck near zero
- RareEngine control calibration that sets the fault too readily
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Easy · Often possible to do yourself.Typical cost: €0 – €300
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.