P05E8Engine Oil Bypass Valve Control Circuit/Open
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- The engine oil bypass valve is an electrically switched solenoid that, according to patents (Hyundai/Kia), routes oil around the oil cooler when cold so the engine warms up faster with less friction, and through the cooler once the oil is hot. It is not the purely mechanical oil filter bypass. CARB requires output components to be checked for circuit faults. No manufacturer document available to us uses P05E8–P05EA, and no vehicle with these codes was found. If the circuit fails, the valve stays in its unpowered position – depending on design oil may run too hot under load or warm up slowly. P05E8 means the control circuit is open: the driver sees missing voltage or high resistance.
- What you may notice
- Check engine light (if rated as emission related)
- Oil too hot under load or slow warm-up, depending on rest position
- Usually no noticeable driving symptoms
- Likely causes
- LikelyConnector at the valve loose, corroded or spread
- PossibleValve solenoid coil open
- PossibleBroken wire in the harness
- RareOutput driver in the module faulty
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Often possible to do yourself.Typical cost: €50 – €350
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.