BMW · DTC LOOKUP

FEM ISN mismatchBMW F-chassis FEM/BDC ISN doesn't match DME

BMW diagnostic code. Below: what it means, common causes, symptoms, and the exact bench-programming fix path.

Common causes

  • FEM/BDC replaced without ISN match
  • DME replaced without ISN match
  • Donor module installed
  • Failed coding attempt

Symptoms you'll see

  • F-chassis BMW won't start
  • FEM-DME comm errors
  • New keys can't be programmed

The fix path

BMW FEM/BDC Key Programming ($150) — ship FEM/BDC + DME together. We read the DME's ISN, write to FEM, then pair a fresh key.

AML services that fix this

Mail in the affected module, we bench-program, ship back next business day. Flat pricing, return shipping included.

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Related diagnostic codes

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