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Home >> Infiniti >> 2021 >> QX80 Premium Select, AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (DTCS) (3 Of 5) >> Engine (ECM) >> DTC P0506: ISC System >> DTC Description >> DTC Detection Logic
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DTC Detection Logic

NOTE: If DTC P0506 is displayed with other DTC, first perform the trouble diagnosis for the other DTC.

DTC No.

Trouble diagnosis name

(Trouble diagnosis content)

DTC detecting condition

Possible cause

P0506

ISC SYSTEM

(Idle speed control system RPM lower than expected)

The idle speed is less than the target idle speed by 100 rpm or more.

  • Electric throttle control actuator
  • Intake air leakage