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Home >> Infiniti >> 2017 >> QX80 Base, RWD >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System (DTCS) (3 Of 4) >> DTC/Circuit Diagnosis >> DTC P1805: Brake Switch >> DTC Logic >> DTC Detection Logic
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DTC Detection Logic

DTC No. Trouble diagnosis name
(Trouble diagnosis content)
DTC detecting condition Possible cause
P1805 BRAKE SW/CIRCUIT
(Brake switch)
A brake switch signal is not sent to ECM for extremely long time while the vehicle is being driven.
  • Harness or connectors

    (Stop lamp switch circuit is open or shorted.)

  • Stop lamp switch