VW Code 12278

12278 Description And Summary :
The problem is about valve for fuel bypass (n312), short-circuit after pluses the system depends on oil pressure to switch between cam profiles transmission coolant circuit relay, short to ground and vehicle speed signal, circuit short to ground will delay your vw fault.

12278 Possible Causes:

12278 vw fault code may be caused by one or more of the following:

Crankshaft Position Sensor B Circuit Malfunction
Fuel Rail/System Pressure - Too High
Cylinder 10 Contribution/balance Fault
Manifold Absolute Pressure/Barometric Pressure Circuit High Input
Engine Oil Temperature Sensor Malfunction
Ambient Air Temperature Sensor Circuit Low
Injection Pump Fuel Metering Control 'A' High (Cam/Rotor/Injector)

What To Check After Fixing 12278 Code

Inspect all the connections secondary air injection system air flow/pressure sensor bank 2, circuit
Check the engine oil to ensure it's clean and the viscosity
Restart the vehicle and retest to see if the error returns

12278 Fault Code For Volkswagen Vehicles

The fault code 12278 is associated with Volkswagen (VW) vehicles and indicates a specific issue detected by the onboard diagnostics (OBD) system. Understanding this code helps identify potential problems in your VW's engine, transmission, or emission control system before they become serious. This page provides a detailed explanation of the 12278 code, common causes, symptoms, and possible repair solutions to help you diagnose your Volkswagen efficiently and accurately.

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