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Home >> Mazda >> 2021 >> CX-9 Signature >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic - Engine Control System (6 Of 6) >> DTC U0284-00: Lin Communication System: Communication Error Between Active Air Shutter And Pcm >> Notes
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DTC U0284-00: Lin Communication System: Communication Error Between Active Air Shutter And Pcm: Notes

DTC U0284:00 DETECTION CONDITION AND POSSIBLE CAUSE

DTC U0284:00 LIN communication system: Communication error between active air shutter and PCM
DETECTION CONDITION
  • PCM detects a communication error between the PCM and active air shutter.

    Diagnostic support note

  • This is an intermittent monitor (other).
  • The check engine light does not illuminate.
  • FREEZE FRAME DATA is not available.
  • Snapshot data is available.
  • DTC is stored in the PCM memory.
FAIL-SAFE FUNCTION
  • Not applicable
POSSIBLE CAUSE
  • LIN communication line malfunction between active air shutter and PCM
  • Active air shutter connector or terminals malfunction
  • Short to ground or open circuit in active air shutter power supply circuit
    • Short to ground in wiring harness between ENGINE 3 15 A fuse and active air shutter terminal A
    • ENGINE3 15 A fuse malfunction
      • Open circuit in wiring harness between main relay terminal C and active air shutter terminal A
  • Open circuit in wiring harness between active air shutter terminal D and body ground
  • PCM connector or terminals malfunction
  • Short to ground in wiring harness between active air shutter terminal C and PCM terminal 2BG
  • Short to power supply in wiring harness between active air shutter terminal C and PCM terminal 2BG
  • Open circuit in wiring harness between active air shutter terminal C and PCM terminal 2BG
  • Active air shutter malfunction
  • PCM malfunction
G13697943Courtesy of MAZDA MOTORS CORP.