P31B7 – BMW DTC

BMW DTC P31B7 – Cylinder 7 H2-Injector High Side Shorted to Coil

DTC P31B7 meaning on BMW

The DTC P31B7 code on a BMW indicates that there is a high side short circuit between the hydrogen injector and the coil in cylinder 7.

BMW DTC P31B7 symptoms

Symptoms of the DTC P31B7 code on a BMW may include rough idling, misfiring, loss of power, and potentially an illuminated check engine light on the dashboard.

BMW DTC P31B7 causes

The main causes of the DTC P31B7 code on a BMW are typically a short circuit between the hydrogen injector and the coil in cylinder 7, wiring issues, or a faulty injector or coil.

BMW DTC P31B7 seriousness

Ignoring the DTC P31B7 code on a BMW can lead to poor engine performance, reduced fuel efficiency, and potential damage to other engine components over time. It is recommended to address this issue promptly.

How to diagnose DTC P31B7 on BMW

To diagnose the DTC P31B7 code on a BMW, a mechanic would typically perform a visual inspection of the wiring harness, test the hydrogen injector and coil in cylinder 7 for continuity and resistance, and use a diagnostic scanner to check for any stored fault codes.

How to fix DTC P31B7 on BMW

Fixing the DTC P31B7 code on a BMW may involve repairing or replacing any damaged wiring, replacing the faulty hydrogen injector or coil in cylinder 7, and clearing the fault codes from the vehicle’s ECU.

How to erase DTC P31B7 on BMW

To erase the DTC P31B7 code on a BMW, a diagnostic scanner can be used to clear the fault code from the vehicle’s ECU. Once the issue has been addressed and fixed, the code can be erased to reset the system.

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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