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Home >> Infiniti >> 2011 >> M37 Base >> Repair and Diagnosis (Single Page) >> External Pages >> Different car >> Section 26 (Security Control System) >> DTC/Circuit Diagnosis >> DTC B2603: Shift Position >> DTC Logic >> DTC Detection Logic
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DTC Detection Logic

WARNING: This page is about a different car, the 2011 Infiniti QX56. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
  • If DTC B2603 is displayed with DTC B2601, first perform the trouble diagnosis for DTC B2601. Refer to "DTC LOGIC ".
DTC DETECTION LOGIC

DTC No. Trouble diagnosis name DTC detecting condition Possible causes
B2603 SHIFT POSI STATUS BCM detects the following status when ignition switch is in the ON position.
  • P position signal from TCM: approx. 0 V
  • A/T shift selector (detention switch) signal: approx. 0 V
  • Harness or connector [A/T shift selector (detention switch) circuit is open or shorted.]
  • Harness or connectors (TCM circuit is open or shorted.)
  • A/T shift selector (detention switch)
  • A/T assembly (TCM)
  • BCM
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