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2021 BMW 740I
3.0L I6 Turbo B58•RWD•AUTOMATIC•gas•B58B30•turbo
2 active safety recalls on this vehicle — view recalls
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Repairs0Labor484Torque1511Fluid8DTC2246Battery1Maintenance0Recalls2
P0279moderate severityPowertrain

Cylinder 9 Injector Circuit Low

on 2021 BMW 740i 3.0L I6 Turbo B58 · RWD

What this code means

The PCM detected a low voltage condition in the injector control circuit for cylinder 9. This usually means an open or shorted injector wire or a failed injector.

Symptoms

  • Engine misfire
  • Rough idle
  • Reduced power

Common causes

  • Faulty fuel injector
  • Open or shorted injector wiring
  • Corroded injector connector
  • Failed PCM injector driver

Diagnostic steps

  1. Scan and confirm code with freeze frame
  2. Inspect injector 9 connector and wiring
  3. Measure injector resistance
  4. Test injector driver signal from PCM
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