Nissan Pathfinder: Steering Control System - Basic Inspection

Nissan Pathfinder (R53) 2022-2025 Service Manual / Steering :: Steering Control System / Basic Inspection

Diagnosis and Repair Work Flow
Additional Service When Replacing Eps Control Unit

Diagnosis and Repair Work Flow Nissan Pathfinder SUV

Work Flow

DETAILED FLOW

INTERVIEW FROM THE CUSTOMER

Clarify customer complaints before inspection. First of all, perform an interview utilizing reproduce symptoms as well as fully understand it. Ask customer about his/her complaints carefully. Check symptoms by driving Nissan Pathfinder vehicle with customer, if necessary.

CAUTION:

Customers are not professional. Never guess easily like “maybe the customer means that...,” or “maybe the customer mentions this symptom”.

GO TO 2.

CHECK SYMPTOM

Reproduce the symptom that is indicated by the customer, based on the information from the customer obtained by interview. Also check that the symptom is not caused by protection function. Refer to Protection Function.

CAUTION:

When the symptom is caused by normal operation, fully inspect each portion and obtain the understanding of customer that the symptom is not caused by a malfunction.

GO TO 3.

CHECK Nissan Pathfinder Vehicle CONDITION

CONSULT

Ignition switch ON.
Check “HEAT PROTECT STATUS“ in “Data Monitor“ mode of “EPS/DAST 3“.

Monitor item Values

HEAT PROTECT STATUS NORMAL

Monitor item	Values
HEAT PROTECT STATUS	NORMAL

Is the inspection result normal?

YES>>

GO TO 4.

NO>>

Wait with the ignition switch OFF until the data monitor indication becomes “NORMAL”. And then GO TO 4.

PERFORM SELF-DIAGNOSIS

CONSULT

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

Is any DTC detected?

YES>>

Record or print DTC and freeze frame data (FFD). GO TO 5.

NO>>

GO TO 7.

RECHECK SYMPTOM

CONSULT

Erase “Self Diagnostic Result” mode of “EPS/DAST 3”.
Perform DTC confirmation procedures for the malfunctioning system.

NOTE:

If some DTCs are detected at the same time, determine the order for performing the diagnosis based on DTC Inspection Priority Chart.

Is any DTC detected?

YES>>

GO TO 6.

NO>>

Check harness and connectors based on the information obtained by interview. Refer to Diagnostic Work Sheet.

REPAIR OR REPLACE MALFUNCTIONING PARTS

Repair or replace malfunctioning components.
Reconnect part or connector after repairing or replacing.
When DTC is detected, erase “Self Diagnostic Result” mode of “EPS/DAST 3”.

GO TO 8.

IDENTIFY MALFUNCTIONING SYSTEM BY SYMPTOM DIAGNOSIS

Estimate malfunctioning system based on symptom diagnosis and perform inspection.

Can the malfunctioning system be identified?

YES>>

GO TO 8.

NO>>

Check harness and connectors based on the information obtained by interview. Refer to Diagnostic Work Sheet.

FINAL CHECK

CONSULT

Check the reference value for EPS control unit.
Recheck the symptom and check that symptom is not reproduced on the same conditions.

Is the symptom reproduced?

YES>>

GO TO 3.

NO>>

Inspection End.

Diagnostic Work Sheet

Description

In general, customers have their own criteria for a problem. Therefore, it is important to understand the symptom and status well enough by asking the customer about his/her concerns carefully. To systemize all the information for the diagnosis, prepare the interview sheet referring to the interview points.
In some cases, multiple conditions that appear simultaneously may cause a DTC to be detected.

Interview sheet sample

Interview sheet
Customer name	MR/MS	Registration number	Initial year registration
Customer name	MR/MS	Nissan Pathfinder Vehicle type	VIN
Storage date		Engine	Mileage	km (Mile)
Symptom		□The steering wheel position (center) is in the wrong position.
		□Warning lamp turns on.
		□Noise □Vibration
		□Others ( )
First occurrence		□Recently □Others ( )
Frequency of occurrence		□Always □Under a certain conditions of □Sometimes (time(s)/day)
Climate conditions		□Irrelevant
	Weather	□Fine □Cloud □Rain □Snow □Others ( )
	Temperature	□Hot □Warm □Cool □Cold □Temperature [Approx. °C (°F)]
	Relative humidity	□High □Moderate □Low
Road conditions		□Urban area □Suburb area □High way □Mountain road (uphill or down hill) □Rough road
Operation conditions, etc.		□Irrelevant □When engine starts □During idling □During driving □During acceleration □At constant speed driving □During deceleration □During cornering (right curve or left curve) □During steering
Other conditions
Memo

Additional Service When Replacing Eps Control Unit Nissan Pathfinder

Work Procedure

DESCRPITION

When replacing the EPS control unit, the procedures of BEFORE REPLACEMENT and AFTER REPLACEMENT must be performed. For work procedure, refer to the following:

Before EPS control unit replacement.
After EPS control unit replacement.

BEFORE REPLACEMENT

When replacing the EPS control unit, save “Operation log”.

AFTER REPLACEMENT

After replacing the EPS control unit, the following items must be performed:

EPS control unit programming
Adjust the neutral position of steering angle sensor.
Register intelligent keys

NOTE:
When replacing EPS control unit, perform the system initialization (NATS).

WORK PROCEDURE (BEFORE REPLACING EPS CONTROL UNIT)

SAVE “OPERATION LOG”

CONSULT

Save “Operation Log”, according to the procedure of “Programming” in CONSULT Operation Manual.

NOTE:

EPS control unit part number is saved in “Operating Log” saved in CONSULT.

Replace the EPS control unit. Refer to Removal and Installation.
After replacing the EPS control unit, perform necessary work.

WORK PROCEDURE (AFTER REPLACING EPS CONTROL UNIT)

CHECK “OPERATION LOG”

CONSULT

Check “Operation Log” saved before replacing the EPS control unit, according to the procedure of “Programming” in CONSULT Operation Manual.

NOTE:

For the Nissan Pathfinder vehicle that the programming is to be performed, check if “Operation Log” of Vehicle Identification Number (VIN) is in Saved Data List.

Is there an applicable Operation Log in the Saved Data List?

YES>>

GO TO 2.

NO>>

GO TO 3.

PERFORM EPS CONTROL UNIT PROGRAMMING

CONSULT

Perform EPS control unit programming, according to “Programming” of CONSULT Operation Manual. Refer to CONSULT Operation Manual.

CAUTION:

During programming, maintain the following conditions:

Ignition switch: ON

Electric load: OFF

Steering wheel: Not steering

Battery voltage: 12 – 13.5 V (Check the value displayed on the CONSULT screen.)

Nissan Pathfinder Vehicle speed: 0 km/h

GO TO 5.

READ IN EPS CONTROL UNIT PART NUMBER BY “FAST LINKED”

Obtain EPS control unit part number by NISSAN PARTS CATALOGUE GLOBAL Web-FAST, according to the procedure of ‘FAST linked’ in CONSULT Operation Manual. Refer to CONSULT Operation Manual.

CAUTION:

Be sure to select “FAST linked”.

NOTE:

“FAST linked” allows an appropriate programming by obtaining ECU part number from NISSAN PARTS CATALOGUE GLOBAL Web-FAST even when the part number cannot be obtained from the old ECU used before replacing with a new one.

GO TO 4.

PERFORM PROGRAMMING (FAST LINKED)

CONSULT

Perform EPS control unit programming according to the procedure of FAST linked in CONSULT Operation Manual. Refer to CONSULT Operation Manual.

CAUTION:

During programming, maintain the following conditions:

Ignition switch: ON

Electric load: OFF

Steering wheel: Not steering

Battery voltage: 12 – 13.5 V (Check the value displayed on the CONSULT screen.)

Nissan Pathfinder Vehicle speed: 0 km/h

GO TO 5.

PERFORM NECESSARY WORK

Perform adjustment of steering angle sensor neutral position. Refer to Work Procedure.
Select "Self Diagnostic Result" mode of "EPS/DAST 3".
Erase "Self Diagnostic Result" mode of "EPS/DAST 3".

GO TO 6.

Register Intelligent Keys. For initialization and registration of Intelligent Key: Refer to CONSULT Immobilizer mode and follow the on-screen instructions.

NOTE:
If customer has Virtual I-Key application, reprogram and register it as a third keyfob, and follow same configuration as Nissan Pathfinder vehicle Intelligent Key.