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2003 INFINITI FX45
4.5L V8•AWD•AUTOMATIC•gas
9 active safety recalls on this vehicle — view recalls
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Repairs0Labor478Torque672Fluid7DTC1782Battery1Maintenance0Recalls9
P1128high severityPowertrain

Throttle Control Motor

on 2003 Infiniti FX45 4.5L V8 · AWD

What this code means

The throttle control motor circuit is faulty and not driving the throttle plate as commanded. Related to generic P2100 throttle actuator motor circuit codes.

Symptoms

  • Check engine light on
  • Limp mode / reduced power
  • No throttle response

Common causes

  • Faulty throttle control motor
  • Wiring or connector fault
  • Blown motor fuse
  • ECM driver failure

Diagnostic steps

  1. Confirm code P1128
  2. Check motor fuse and power supply
  3. Test motor resistance and wiring
  4. Replace throttle body if faulty
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