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Home >> Infiniti >> 2024 >> QX55 Essential >> Repair and Diagnosis (Single Page) >> Steering >> Steering Control Systems >> Steering Control System (Electric Power Steering) (DTC/Circuit Diagnosis) >> DTC/Circuit Diagnosis >> C1607, C1608 Power Steering Control Module >> DTC Description
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DTC Description

DTC DETECTION LOGIC 

DTC No. CONSULT screen terms(Trouble diagnosis content) DTC detected condition
C1607 EEPROM(EEPROM) Diagnosis condition When engine running.
Signal (terminal) -
Threshold Malfunction of EPS control unit memory (EEPROM) function
Diagnosis delay time Less than 1 second
C1608 CONTROL UNIT(Control unit) Diagnosis condition When engine running.
Signal (terminal) -
Threshold Internal malfunction of EPS control unit
Diagnosis delay time 1 seconds or more

POSSIBLE CAUSE 

EPS control unit

FAIL-SAFE 

DTC Fail-safe condition
C1607 Constant steering state
C1608 Manual steering state

DTC CONFIRMATION PROCEDURE 

  1. PRECONDITIONING 
    1. If "DTC CONFIRMATION PROCEDURE" has been previously conducted, always place ignition switch OFF and wait at least 10 seconds before conducting the next test.

    >>

    GO TO 2.

  2. DTC REPRODUCTION PROCEDURE 
    1. SYMBOL CONSULT
      1. Start the engine.
        CAUTION:

        Never drive the vehicle.

      2. Select "Self Diagnostic Result" mode of "EPS/DAST 3".

    Is DTC "C1607" or "C1608" detected?

    YES>>

    Proceed to diagnosis procedure. Refer to DTC Diagnosis Procedure .

    NO>>

    To check malfunction symptom before repair: Refer to Intermittent Incident .

    NO>>

    Confirmation after repair: Inspection End.