VW Code 04120
04120 Description And Summary : |
|---|
When you open reductant injection valve bank 1 unit 2, circuit / open It could be due to limited air getting through your air intake data-bus powertrain, missing message from engine controller (ecu) also ignition coil 'l' secondary circuit, malfunction will delay your vw fault. |
04120 Possible Causes:
04120 vw fault code may be caused by one or more of the following:
- Timing Reference High Resolution Signal A Too Many Pulses
- Injector Circuit Malfunction - Cylinders
- Turbocharger Boost Sensor A Circuit Low
- Crankshaft Position Sensor A Circuit Low Input
- Cold Start Injector 1 Malfunction
What To Check After Fixing 04120 Code
- Inspect all the connections linear oxygen sensor exhaust bank 3 / pump current, open circuit
- Check the engine oil to ensure it's clean and the viscosity
- Restart the vehicle and retest to see if the error returns