C0478 BMW Fault Code
Check C0478 OBD Fault Code ReasonThe issue covered by the bulletin involves a power steering noise/whine or fluid leak from the power steering pump, gear or high pressure side power steering hose during extreme low outdoor temperature operation.
C0478 Code Symptoms :
When you turn on the ignition, the Service Engine Soon or Check Engine C0478 light should flash briefly, indicating that the OBD system is ready to scan your vehicle for any malfunctions. After this brief flash, the light should stay off while you drive as long as no problems are detected. If so, you'll be glad to know that your vehicle is equipped with an early warning system that could save you time, money, and fuel in addition to helping protect the C0478!
Diagnosis And Repairing C0478
C0478 OBD2 specifically refers to the camshaft (cam) timing. In this case, if the cam timing is over-retarded, the engine light will be illluminated and the code will be set.
How to fix C0478 code ?
- Continuous oil flow to the VCT piston chamber
- Damaged VCT phaser
- Insufficient cylinders compression
- Fuel filler cap remains open or fails to close
