Diagnosis and Repair Work Flow

Work Flow

Work Flow

DETAILED FLOW

1. INTERVIEW FROM THE CUSTOMER

   1. Clarify customer complaints before inspection. First of all, perform an interview utilizing, refer to Diagnostic Work Sheet, and reproduce symptoms to understand them fully. Ask customer about his/her complaints carefully. Check symptoms by driving Nissan Sentra vehicle with customer, if necessary.

      CAUTION:

      Customers are not professional. Never make assumptions like “maybe the customer means that...,” or “maybe the customer mentioned this symptom”.

   >>

   GO TO 2.

2. CHECK SYMPTOM

   1. 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 Fail-Safe.

      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.

3. CHECK Nissan Sentra Vehicle CONDITION

   1. CONSULT

      1. Ignition switch ON.

      2. Select “ECU temperature” in "Data Monitor" mode of "EPS/DAST 3".

         Monitor item	Values
         ECU temperature	194°F (90°C) or less

   Is the inspection result normal?

   YES>>

   GO TO 4.

   NO>>

   Wait with the ignition switch OFF until the “Data Monitor” indication becomes 194 °F (90 °C) or less. Go to 4 after the temperature drops to 194 °F (90 °C) or less.

4. PERFORM SELF DIAGNOSTIC RESULT

   1. 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.

5. RECHECK SYMPTOM

   1. CONSULT

      1. Erase "Self Diagnostic Result" mode of "EPS/DAST 3".

      2. 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. Refer to DTC Inspection Priority Chart.

   Is any DTC detected?

   YES >>

   GO TO 6.

   NO >>

   Check harness and connectors based on the information obtained by interview.

6. REPAIR OR REPLACE THE MALFUNCTIONING COMPONENTS.

   1. CONSULT

      • Repair or replace the 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.

7. IDENTIFY THE MALFUNCTIONING SYSTEM BY SYMPTOM DIAGNOSIS

   1. Estimate the 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.

8. FINAL CHECK

   1. CONSULT

      1. Check the reference value for EPS control unit.

      2. 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

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
		Nissan Sentra Vehicle type		VIN
Storage date		Engine		Mileage	Mile (km)
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.     °F (°C)]
	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. Work Procedure

Work Procedure

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 chassis control module (with built in steering angle sensor).

WORK PROCEDURE (BEFORE REPLACING EPS CONTROL UNIT)

1. SAVE “OPERATION LOG”

   1. CONSULT

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

      Note:

      EPS control unit part number is saved in “Operation 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)

1. CHECK “OPERATION LOG”

   1. 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 Sentra 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.

2. PERFORM EPS CONTROL UNIT PROGRAMMING

   1. 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 Sentra Vehicle speed: 0 MPH

   >>

   GO TO 5.

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

   1. 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.

4. PERFORM PROGRAMMING (FAST LINKED)

   1. 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 Sentra Vehicle speed: 0 MPH

   >>

   GO TO 5.

5. PERFORM NECESSARY WORK

   1. 1. Perform adjustment of chassis control module (with built in steering angle sensor) neutral position. Refer to Work Procedure.

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

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

   >>

   End of work.