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Home >> Infiniti >> 2013 >> M56 x >> Repair and Diagnosis >> Steering >> Power Steering >> Steering Control System (With 4WAS) >> System Description >> System >> 4WAS System >> 4WAS SYSTEM: Fail-safe (4WAS Front Control Unit)
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4WAS SYSTEM: Fail-safe (4WAS Front Control Unit)

4WAS system enters in the fail-safe mode (4WAS system is stopped), and 4WAS warning lamp turns ON (except DTC "C1633") if an error is detected in 4WAS system component part.

DTC Error area and root cause Contents of fail-safe
C1621 4WAS front motor current valve error is detected.
(4WAS front motor current valve is excessively large.)
4WAS system is stopped.
C1622 4WAS front motor voltage valve or current error valve is detected.
(4WAS front motor voltage valve error is detected.)
(Voltage valve or current valve error is detected when starting the system.)
C1627 The indication value from 4WAS front actuator (front wheel angle) differs from the value from 4WAS front control unit.
C1628 The front wheel steering angle sensor error is detected.
C1631 An error is detected inside 4WAS front control unit.
C1632 An error is detected inside 4WAS front control unit.
C1633 An error is detected inside 4WAS front control unit.
C1651 The ignition voltage signal error is detected.
C1652 4WAS front motor main power supply error is detected.
C1654 An error is detected on the main relay power supply inside 4WAS front control unit.
C1655 4WAS front motor 3-phase current error is detected. (Current is not applied to 4WAS front motor)
C1661 4WAS front lock solenoid valve error is detected. (An electric activation error is detected.)
C1667 4WAS front lock solenoid valve (lock) error is detected. (An error is detected in lock condition.)
C1668 4WAS front lock solenoid valve (lock) error is detected. (Excessive force is applied to the lock.)
C1669 4WAS front actuator error is detected. (An error is detected in unlock condition.)
C1671 4WAS front actuator adjustment is not performed.
C1672 4WAS front actuator adjustment is incomplete.
C1684 4WAS communication line(1) data communication error is detected. (An error signal is detected from 4WAS main control unit.)
C1685 4WAS communication line(1) data communication error is detected. (An error signal is detected from 4WAS main control unit.)
C1686 An error is detected on 4WAS main control unit side. (4WAS main control unit fail-safe mode)
U1000 When 4WAS front control unit is not transmitting or receiving 4WAS communication signal for 2 seconds or more.
U1002 When 4WAS front control unit is not transmitting or receiving 4WAS communication signal for 2 seconds or less.
U1010 When detecting error during the initial diagnosis of 4WAS controller of 4WAS front control unit
(1) Communication line between 4WAS front control unit and 4WAS main control unit