EA4 NTC 0x0A1 Kinematic Integrity Fault

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NTC Overview
NTC 0x0A1  Kinematic Integrity Fault

Description:


This diagnostic is responsible for detecting  a condition of failed mechanical integrity between the input shaft and output shaft, where the motor coupling may have broken free from the assist mechanism and the motor starts spinning freely.  

Diagnostic Overview:

  • •This diagnostic monitors cumulative motor position (scaled to hw deg) and if this hw position exceeds a calibratable threshold ~ (maximum rack travel + tolerance), the NTC is set. 

  • •This is not a recoverable fault.
     

Typical Fault Response:  F3 fault type.

  • •Since motor is free spinning, the hand wheel position is not known for those systems that use motor position to help with Handwheel angle calculations.  In such cases Handwheel angle dependent functions need to be disabled.  
     

Probable Sources
(Most to Least Probable):

    • •Motor Rotations not constrained mechanically 

      • •Not connected to a R & P gear 

      • •Mechanical failure 

Initialization

 

Periodic

X

Event

 

Date

Revision

Initials

06-13-16

Initial Release

SS

   
   
   
   
   
   
   
   
   

Description of Unusual Event setting NTC

Root Cause / Explanation

  
  
  

Date

FDD & Rev

Modifications to Diagnostic Function

06-13-16

SF045A, V2.0.0

Initial release

   
   
   

Algorithm Changes / Lessons Learned / Revision Log

Last modified October 12, 2025: Initial commit (1fadfc4)