BMW DTC P31DD – H2 and High Pressure Injector ECM Boost Voltage Too Low (Bank 2)
DTC P31DD meaning on BMW
The DTC P31DD on a BMW indicates that there is an issue with the High-Pressure Injector ECM Boost Voltage being too low in Bank 2 of the engine. This fault code is specific to BMW vehicles and is related to the fuel injection system.
BMW DTC P31DD symptoms
Symptoms of the DTC P31DD on a BMW may include rough idling, engine misfires, loss of power, decreased fuel efficiency, and potentially an illuminated check engine light on the dashboard.
BMW DTC P31DD causes
The causes of the DTC P31DD on a BMW can vary, but common reasons include a faulty high-pressure fuel injector, issues with the fuel delivery system, wiring or connector problems, or a malfunctioning Engine Control Module (ECM).
BMW DTC P31DD seriousness
The DTC P31DD is a serious fault code as it directly affects the fuel delivery and combustion process in the engine. Ignoring this issue can lead to further engine damage and potentially unsafe driving conditions.
How to diagnose DTC P31DD on BMW
To diagnose the DTC P31DD on a BMW, a mechanic would typically use a diagnostic scanner to retrieve the fault codes and then perform a thorough inspection of the high-pressure fuel injector system, wiring, connectors, and ECM to identify the root cause of the issue.
How to fix DTC P31DD on BMW
Fixing the DTC P31DD on a BMW may involve replacing the faulty high-pressure fuel injector, repairing any wiring or connector issues, or reprogramming the Engine Control Module (ECM) if necessary. It is recommended to have this repair performed by a qualified automotive technician.
How to erase DTC P31DD on BMW
Once the underlying issue causing the DTC P31DD on a BMW has been fixed, the fault code can be erased using a diagnostic scanner that has the capability to clear fault codes. This will reset the check engine light and ensure that the repair was successful.
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
Some of the links on this page may be affiliate links, which means we may earn a small commission if you make a purchase. This helps us keep our DTC database up to date and provide valuable content for free. We only recommend products that we have tested and believe to be the best in their class.