Nissan Sentra Service Manual: ECU diagnosis information

Nissan Sentra Service Manual / Steering / Steering control system / ECU diagnosis information

EPS control unit

Reference Value

VALUES ON THE DIAGNOSIS TOOL

The following table includes information (items) inapplicable to this vehicle. For information (items) applicable to this vehicle, refer to CONSULT display items.

CAUTION:

The output signal indicates the EPS control unit calculation data. The normal values will be displayed even in the event that the output circuit (harness) is open.

*1: Almost in accordance with the value of вЂњMOTOR SIGвЂќ. It is

*1: Almost in accordance with the value of вЂњMOTOR SIGвЂќ. It is not a malfunction though these values are not accorded when steering quickly.

*2: A fixed value is indicated regardless of steering turning.

*3: Normally displays 100%. In case of an excessive stationary steering, the assist curvature gradually falls.

However, it returns to 100% when left standing.

*4: It is not a malfunction, though it might not be corresponding just after ignition switch in turned ON.

Terminal layout

Physical values

Physical values

Fail-Safe

Fail-Safe

If any malfunction occurs in the system and control unit detects the malfunction, eps warning lamp on combination meter turns on to indicate system malfunction.
When eps warning lamp is on, the system enters into a manual steering state. (Control turning force steering wheel becomes heavy.)
Under abnormal vehicle speed signal conditions, vehicle speed is judged as constant.

Protection Function

Eps control unit decreases the output signal to eps motor while extremely using the power steering function (e.G., Full steering) consecutively for protecting eps motor and eps control unit (overload protection control).

While activating overload protection control, the assist torque gradually decreases, and the steering wheel Turning force becomes heavy. The normal assist torque is recovered if the steering wheel is not turned for a while.

DTC Inspection Priority Chart

When multiple dtcs are detected simultaneously, check one by one depending on the following priority list.

DTC Index

DTC Index

*: Even if dtc is detected, eps warning lamp does not turn on

*: Even if dtc is detected, eps warning lamp does not turn on when assist torque is generated.

Diagnosis system (EPS control unit)

CONSULT Function FUNCTION CONSULT can display each diagnostic item using the diagnostic test modes shown following. Diagnostic test mode Function ECU identification The part ...

Wiring diagram

Power steering control system Wiring Diagram ...

Other materials:

Power supply and ground circuit
Av control unit Av control unit : diagnosis procedure Regarding wiring diagram information, refer to av-331, "wiring diagram". 1.Check fuse Check that the following fuses are not blown. Are the fuses blown? Yes >> replace the blown fuse after repairing the affected circuit. ...

Power supply and ground circuit
Body control system Body control system : diagnosis procedure Regarding wiring diagram information, refer to bcs-51, "wiring diagram". 1.Check fuses and fusible link Check that the following fuses and fusible link are not blown. Is the fuse blown? Yes >> replace the blown f ...

Diagnosis system (ECM)
Diagnosis description : 1st trip detection logic and two trip detection logic When a malfunction is detected for the first time, 1st trip DTC and 1st trip Freeze Frame data are stored in the ECM memory. The MIL will not illuminate at this stage. <1st trip> If the same malfunction is dete ...