BMW DTC P31C4 – Cylinder 3 H2-Injector or High Pressure Injector High Side Circuit Low
DTC P31C4 meaning on BMW
The DTC P31C4 fault code on a BMW indicates an issue with the Cylinder 3 H2-Injector or High Pressure Injector High Side Circuit being detected as low. This means that there is a problem with the fuel injector or its high-pressure circuit in cylinder 3 of the engine.
BMW DTC P31C4 symptoms
Symptoms of the DTC P31C4 fault code on a BMW may include rough idling, misfiring, loss of power, decreased fuel efficiency, and potentially an illuminated check engine light on the dashboard.
BMW DTC P31C4 causes
The causes of the DTC P31C4 fault code on a BMW can vary, but common reasons include a faulty high-pressure fuel injector, wiring issues in the injector circuit, or a problem with the engine control module (ECM).
BMW DTC P31C4 seriousness
The seriousness of the DTC P31C4 fault code on a BMW depends on the underlying cause. Ignoring this fault code can lead to poor engine performance, potential damage to the catalytic converter, and increased emissions.
How to diagnose DTC P31C4 on BMW
To diagnose the DTC P31C4 fault code on a BMW, a mechanic would typically use a diagnostic scanner to retrieve the code and then perform a visual inspection of the high-pressure injector in cylinder 3. They may also test the wiring and connections related to the injector to identify any faults.
How to fix DTC P31C4 on BMW
Fixing the DTC P31C4 fault code on a BMW usually involves replacing the faulty high-pressure fuel injector in cylinder 3. Additionally, any damaged wiring or connectors should be repaired or replaced. After the repairs are completed, the fault code should be cleared from the ECM memory.
How to erase DTC P31C4 on BMW
To erase the DTC P31C4 fault code on a BMW, a diagnostic scanner can be used to clear the code from the engine control module (ECM) memory. Once the repairs have been made and the issue resolved, the fault code can be erased to reset the system and turn off the check engine light.
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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