P31E1 – BMW DTC

BMW DTC P31E1 – H2 and High Pressure Injector ECM Supply Voltage High (Bank 2)

DTC P31E1 meaning on BMW

DTC P31E1 for BMW refers to ¨High Pressure Injector ECM Supply Voltage High (Bank 2).¨ This diagnostic trouble code indicates that the Engine Control Module (ECM) has detected a high voltage condition in the supply voltage circuit for the high-pressure fuel injector in Bank 2 of the engine.

BMW DTC P31E1 symptoms

Symptoms of DTC P31E1 in a BMW may include:

  • Check Engine Light illuminated on the dashboard
  • Engine running rough or misfiring
  • Reduced engine performance
  • Increased fuel consumption

BMW DTC P31E1 causes

Common causes of DTC P31E1 in a BMW include:

  • Faulty high-pressure fuel injector in Bank 2
  • Short circuit or open circuit in the injector supply voltage wiring
  • Faulty Engine Control Module (ECM)
  • Intermittent electrical connection issues

BMW DTC P31E1 seriousness

DTC P31E1 should be addressed promptly as it can lead to engine performance issues and potential damage if left unresolved. Ignoring this fault may result in poor fuel economy, rough running engine, and potential engine damage over time.

How to diagnose DTC P31E1 on BMW

To diagnose DTC P31E1 on a BMW, a mechanic may perform the following steps:

  1. Use a diagnostic scanner to retrieve the fault codes and freeze frame data
  2. Inspect the wiring harness and connectors for any visible damage or corrosion
  3. Test the high-pressure fuel injector in Bank 2 for proper operation
  4. Check the supply voltage to the injector using a multimeter
  5. Perform a continuity test on the wiring to check for any open circuits

How to fix DTC P31E1 on BMW

To fix DTC P31E1 on a BMW, the following steps may be taken:

  1. Replace the faulty high-pressure fuel injector in Bank 2
  2. Repair any damaged wiring or connectors in the supply voltage circuit
  3. If the ECM is found to be faulty, replace it with a new one
  4. Clear the fault codes and perform a test drive to ensure the issue has been resolved

How to erase DTC P31E1 on BMW

To erase DTC P31E1 on a BMW, follow these steps:

  1. Use a diagnostic scanner to clear the fault codes stored in the ECM
  2. Perform a test drive to ensure the Check Engine Light does not reappear
  3. If the fault code returns, further diagnosis and repairs may be necessary

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.