BMW DTC P120A – Crankcase Ventilation Diagnostic Valve Circuit High
DTC P120A meaning on BMW
The DTC P120A code on a BMW indicates an issue with the Crankcase Ventilation Diagnostic Valve Circuit being too high. This valve is responsible for regulating the flow of gases from the crankcase to the intake manifold, helping to maintain proper engine performance and emissions control.
BMW DTC P120A symptoms
Symptoms of a DTC P120A on a BMW may include rough idling, decreased engine performance, increased fuel consumption, and potentially the illumination of the check engine light on the dashboard.
BMW DTC P120A causes
The high circuit condition of the Crankcase Ventilation Diagnostic Valve in a BMW can be caused by wiring issues, a faulty valve itself, or problems with the engine control module (ECM).
BMW DTC P120A seriousness
While a DTC P120A may not cause immediate engine failure, it can lead to decreased performance and increased emissions. Ignoring this issue can potentially cause further damage to the engine over time.
How to diagnose DTC P120A on BMW
To diagnose a DTC P120A on a BMW, a mechanic would typically use a diagnostic scanner to retrieve the fault codes stored in the ECM. They would then inspect the wiring and connections related to the Crankcase Ventilation Diagnostic Valve for any signs of damage or corrosion.
How to fix DTC P120A on BMW
Fixing a DTC P120A on a BMW may involve repairing or replacing any damaged wiring, testing and potentially replacing the Crankcase Ventilation Diagnostic Valve, or addressing any issues with the engine control module. It is recommended to follow the manufacturer’s diagnostic and repair procedures.
How to erase DTC P120A on BMW
Once the underlying issue causing the DTC P120A on a BMW has been resolved, the fault codes can be cleared using a diagnostic scanner. This will reset the check engine light and allow the vehicle’s ECM to monitor the system for any new faults.
Recommended tools & DTC Scanners for BMW
Best Diagnostic App for modern BMWs: BimmerLink
Recommended Bluetooth adapter for Bimmerlink: OBDLink CX
Cable adapter for Bimmerlink: Enet Cable USB Type C
For older BMWs we recommend: Autel AutoLink AL319 (2024 version)
Easy-to-use Multimeter for reliable diagnostics: AstroAI Auto-ranging Multimeter
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