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Home >> Infiniti >> 2018 >> QX30 Essential, AWD >> Repair and Diagnosis (Single Page) >> Steering >> Steering Control Systems >> Steering Control System (DTC/Circuit Diagnosis) >> DTC/Circuit Diagnosis >> DTC P0635: Control Unit >> DTC Description >> DTC Detection Logic
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DTC Detection Logic

DTC

CONSULT screen terms

MELCO code

DTC detection condition

(Trouble diagnosis content)

[Malfunction type]

P0635

06

EPS malfunction

(The electric power steering has a malfunction.)

[ALGORITHM BASED ERROR]

AC, B3, B4, B5,

B0, B1, B6, B7, C0, C1, C2, C3, C4, C5, C6, C8, C9, CA, CB, CC, CD, CE, CF

Diagnosis condition

Ignition switch ON

Signal (terminal)

--

Threshold

Control unit detects internal malfunction.

Diagnosis delay time

0.016 seconds

P0635

06

EPS malfunction

(The electric power steering has a malfunction.)

[ALGORITHM BASED ERROR]

B2

Diagnosis condition

Ignition switch ON

Signal (terminal)

--

Threshold

Control unit detects internal malfunction.

Diagnosis delay time

0.24 seconds

P0635

06

EPS malfunction

(The electric power steering has a malfunction.)

[ALGORITHM BASED ERROR]

9C

Diagnosis condition

Ignition switch ON

Signal (terminal)

--

Threshold

Control unit detects internal malfunction.

Diagnosis delay time

0.048 seconds

P0635

06

EPS malfunction

(The electric power steering has a malfunction.)

[ALGORITHM BASED ERROR]

D8

Diagnosis condition

Ignition switch ON

Signal (terminal)

--

Threshold

Control unit detects internal malfunction.

Diagnosis delay time

0.02 seconds

P0635

06

EPS malfunction

(The electric power steering has a malfunction.)

[ALGORITHM BASED ERROR]

D9

Diagnosis condition

Ignition switch ON

Signal (terminal)

--

Threshold

Control unit detects internal malfunction.

Diagnosis delay time

2 seconds

P0635

06

EPS malfunction

(The electric power steering has a malfunction.)

[ALGORITHM BASED ERROR]

DA

Diagnosis condition

Ignition switch ON

Signal (terminal)

--

Threshold

Control unit detects internal malfunction.

Diagnosis delay time

1 second

P0635

06

EPS malfunction

(The electric power steering has a malfunction.)

[ALGORITHM BASED ERROR]

DB

Diagnosis condition

Ignition switch ON

Signal (terminal)

--

Threshold

Control unit detects internal malfunction.

Diagnosis delay time

0.24 seconds

P0635

06

EPS malfunction

(The electric power steering has a malfunction.)

[ALGORITHM BASED ERROR]

DC

Diagnosis condition

Ignition switch ON

Signal (terminal)

--

Threshold

Control unit detects internal malfunction.

Diagnosis delay time

0.2 seconds

P0635

06

EPS malfunction

(The electric power steering has a malfunction.)

[ALGORITHM BASED ERROR]

DE

Diagnosis condition

Ignition switch ON

Signal (terminal)

--

Threshold

Control unit detects internal malfunction.

Diagnosis delay time

0.004 seconds

P0635

09

EPS malfunction

(The electric power steering has a malfunction.)

[COMPONENT MALFUNCTION]

76

Diagnosis condition

Engine running

Signal (terminal)

--

Threshold

Battery terminal voltage > 3 V

Diagnosis delay time

0.052 seconds

P0635

09

EPS malfunction

(The electric power steering has a malfunction.)

[COMPONENT MALFUNCTION]

57

Diagnosis condition

Initial check

Signal (terminal)

--

Threshold

Motor terminal voltage < 0.75 V

Diagnosis delay time

0.012 seconds

P0635

09

EPS malfunction

(The electric power steering has a malfunction.)

[COMPONENT MALFUNCTION]

56

Diagnosis condition

Ignition switch ON

Signal (terminal)

--

Threshold

Control unit detects the following condition.

  • Internal temperature > 184 deg.C (363.2 deg.F)
  • Internal temperature <-50 deg.C (-58 deg.F)
  • Output voltage > 4.9 V
  • Output voltage < 0.1 V

Diagnosis delay time

0.2 seconds

P0635

09

EPS malfunction

(The electric power steering has a malfunction.)

[COMPONENT MALFUNCTION]

A0, A5, A8, 70, 87

Diagnosis condition

Ignition switch ON

Signal (terminal)

--

Threshold

Control unit detects internal malfunction.

Diagnosis delay time

0.016 seconds

P0635

09

EPS malfunction

(The electric power steering has a malfunction.)

[COMPONENT MALFUNCTION]

77, 86

Diagnosis condition

8.5 V < Battery terminal voltage < 19.2 V

Signal (terminal)

--

Threshold

Control unit detects internal malfunction.

Diagnosis delay time

0.048 seconds

P0635

09

EPS malfunction

(The electric power steering has a malfunction.)

[COMPONENT MALFUNCTION]

84, 90, 91, 93, 94

Diagnosis condition

Ignition switch ON

Signal (terminal)

--

Threshold

Control unit detects internal malfunction.

Diagnosis delay time

0.02 seconds

P0635

09

EPS malfunction

(The electric power steering has a malfunction.)

[COMPONENT MALFUNCTION]

95, 96

Diagnosis condition

Ignition switch ON

Signal (terminal)

--

Threshold

Control unit detects internal malfunction.

Diagnosis delay time

0.016 seconds

P0635

09

EPS malfunction

(The electric power steering has a malfunction.)

[COMPONENT MALFUNCTION]

36

Diagnosis condition

Ignition switch ON

Signal (terminal)

--

Threshold

Control unit detects internal malfunction.

Diagnosis delay time

0.15 seconds

P0635

43

EPS malfunction

(The electric power steering has a malfunction.)

[SPECIAL MEMORY ERROR]

55

Diagnosis condition

Ignition switch ON

Signal (terminal)

--

Threshold

Control unit detects internal malfunction.

Diagnosis delay time

1 time

P0635

45

EPS malfunction

(The electric power steering has a malfunction.)

[PROGRAM MEMORY ERROR]

A2a

Diagnosis condition

Ignition switch ON

Signal (terminal)

--

Threshold

Control unit detects internal malfunction.

Diagnosis delay time

1 time

P0635

45

EPS malfunction

(The electric power steering has a malfunction.)

[PROGRAM MEMORY ERROR]

A2b

Diagnosis condition

Ignition switch ON

Signal (terminal)

--

Threshold

Control unit detects internal malfunction.

Diagnosis delay time

0.016 seconds

P0635

49

EPS malfunction

(The electric power steering has a malfunction.)

[INTERNAL ELECTRONIC ERROR]

52

Diagnosis condition

After the initial check finishes and motor relay is turned ON

Signal (terminal)

--

Threshold

Control unit detects internal malfunction.

Diagnosis delay time

Immediately

P0635

98

EPS malfunction

(The electric power steering has a malfunction.)

[COMPONENT/SYS OVER TEMP]

71

Diagnosis condition

All the time while wake-up by CAN

Signal (terminal)

--

Threshold

Control unit detects high internal temperature.

Diagnosis delay time

1second