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Home >> Infiniti >> 2021 >> QX50 Essential, FWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (DTC/Circuit Diagnosis) (4 Of 5) >> DTC/Circuit Diagnosis >> DTC P1572: Brake Pedal Position Switch >> DTC Description >> DTC Detection Logic
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DTC Detection Logic

NOTE: This self-diagnosis has the one trip detection logic. When malfunction A is detected, DTC is not stored in ECM memory. And in that case, 1st trip DTC and 1st trip freeze frame data are displayed. 1st trip DTC is erased when ignition switch OFF. And even when malfunction A is detected in two consecutive trips, DTC is not stored in ECM memory.

DTC

CONSULT screen terms

(Trouble diagnosis content)

DTC detection condition

P1572

00

ASCD BRAKE SW

(ASCD BRAKE SW)

A

Diagnosis condition

Vehicle speed: More than 30 km/h (19 MPH)

Signal (terminal)

  • Brake pedal position switch signal
  • Stop lamp switch signal

Threshold

ON signals from the stop lamp switch and the brake pedal position switch are sent to the ECM at the same time

Diagnosis delay time

--

B

Diagnosis condition

Vehicle speed: More than 30 km/h (19 MPH)

Signal (terminal)

Brake pedal position switch signal

Threshold

Brake pedal position switch signal is not sent to ECM for extremely long time

Diagnosis delay time

--