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Home >> Infiniti >> 2013 >> M35h >> Repair and Diagnosis >> External Pages >> Different car >> Section 4 (Hybrid Control System) >> DTC/Circuit Diagnosis >> DTC P31F9, P31FA: ASCD Steering Switch >> DTC Logic >> DTC Detection Logic
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DTC Detection Logic

WARNING: This page is about a different car, the 2012 Infiniti M35h. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: If DTC P31F9 or P31FA is displayed with DTC P0A1D, first perform the trouble diagnosis for DTC P0A1D. Refer to "DTC LOGIC ".
DTC DETECTION LOGIC - WITHOUT ICC MODELS

DTC No. Trouble diagnosis name (Trouble diagnosis content) DTC detecting condition Possible cause
P31F9 ASCD SWITCH
(ASCD steering switch)
When the input signal system from ASCD steering switch is abnormal
  • Harness or connectors (ASCD steering switch circuit is open or shorted.)
  • ASCD steering switch
P31FA ASCD SWITCH
(ASCD steering switch)
DTC DETECTION LOGIC - WITH ICC MODELS

DTC No. Trouble diagnosis name (Trouble diagnosis content) DTC detecting condition Possible cause
P31F9 ASCD SWITCH
(ICC steering switch)
When the input signal system from ICC steering switch is abnormal
  • Harness or connectors (ICC steering switch circuit is open or shorted.)
  • ICC steering switch
P31FA ASCD SWITCH
(ICC steering switch)