Nissan Sentra B18 (2020-2025) Service Manual: Additional Service When Replacing Control Unit

Ecm

Description

Performing the following procedure can automatically activate recommunication of ECM and BCM, but only when the ECM is replaced with a new one*.

*: New one means an ECM that has never been energized on-board.

(In this step, initialization procedure using CONSULT is not necessary)

CAUTION:

When replacing the ECM, a new ECM must be used. The functions controlled by the ECM do not operate properly if a ECM from another Nissan Sentra vehicle is used.

• When the replaced ECM is not a brand new, the specified procedure (Initialization of Intelligent Key Unit and registration of Intelligent Keys) using CONSULT is necessary.

• If multiple keys are attached to the key holder, separate them before beginning work.

• Distinguish keys with unregistered key IDs from those with registered IDs.

Work Procedure

1. PERFORM ECM RECOMMUNICATING FUNCTION

   1. 1. Install ECM.

      2. Contact backside of the registered Intelligent Key* to push-button ignition switch while brake pedal is depressed, then ignition switch ON.

         *: To perform this step, use the key that is used before performing ECM replacement.

      3. Maintain ignition switch in the ON position for at least 5 seconds.

      4. Ignition switch OFF.

      5. Check that the engine starts.

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   GO TO 2.

2. PERFORM ADDITIONAL SERVICE WHEN REPLACING ECM

   1. Perform additional service when replacing ECM. Refer to Work Procedure.

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   Inspection End

Bcm

Description

BEFORE REPLACEMENT

When replacing BCM, save or print current vehicle specification with CONSULT configuration before replacement.

CAUTION:

When replacing the BCM, a new BCM must be used. The functions controlled by the BCM do not operate properly if a BCM from another Nissan Sentra vehicle is used.

If “Before Replace ECU” cannot be used, use the “After Replace ECU” or “Manual Configuration” after replacing BCM.

AFTER REPLACEMENT

CAUTION:

• When replacing BCM, you must perform “After Replace ECU” with CONSULT.

  • Complete the procedure of “After Replace ECU” in order.

  • If you set incorrect “After Replace ECU”, incidents might occur.

  • Configuration is different for each Nissan Sentra vehicle model. Confirm configuration of each vehicle model.

Work Procedure

1. SAVING VEHICLE SPECIFICATION

   1. CONSULT

      Enter "Re/Programming, Configuration" and perform “Before Replace ECU” to save or print current Nissan Sentra vehicle specification.

      Note:

      If “Before Replace ECU” cannot be used, use the "After Replace ECU" or "Manual Configuration" after replacing BCM.

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   GO TO 2.

2. REPLACE BCM

   1. Replace BCM. Refer to Removal and Installation.

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   GO TO 3.

3. WRITING Nissan Sentra Vehicle SPECIFICATION

   1. CONSULT

      1. Enter "Re/Programming, Configuration".

      2. If “Before Replace ECU” operation was performed, automatically an "Operation Log Selection" screen will be displayed. Select the applicable file from the "Saved Data List" and press “Confirm” to write Nissan Sentra vehicle specification. Refer to Work Procedure.

      3. If “Before Replace ECU” operation was not performed, select "After Replace ECU" or "Manual Configuration" to write Nissan Sentra vehicle specification. Refer to Work Procedure.

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   Work End.

Intelligent Key Unit

Work Procedure

Perform the following operations when replacing Intelligent Key unit.

CAUTION:

When replacing the Intelligent Key unit, always replace it with a new one. The functions controlled by the Intelligent Key unit does not operate properly in case of reuse of the Intelligent Key unit from another Nissan Sentra vehicle.

BEFORE REPLACEMENT

When replacing Intelligent Key unit, save or print current Nissan Sentra vehicle specification with CONSULT before replacement.

If “Before ECU Replacement” of “Nissan Sentra Vehicle Configuration” cannot be used, use the “Manual Configuration” after replacing Intelligent Key unit.

AFTER REPLACEMENT

CAUTION:

When after replacing Intelligent Key unit, always perform “Operation Log Selection” or “Manual Configuration” with CONSULT. Or not doing so, Intelligent Key unit control function does not operate normally.

When replacing Intelligent Key unit, perform the system initialization (NATS).

1. SAVING Nissan Sentra Vehicle SPECIFICATION

   1. CONSULT

      1. Select “Re/programming, Configuration”.

      2. Select the operation according to the CONSULT screen.

      3. Perform “Before ECU Replacement” of “Nissan Sentra Vehicle Configuration” to write vehicle specification.

      Note:

      If “Before ECU Replacement” of “Nissan Sentra Vehicle Configuration” cannot be used, use the “Manual Configuration” after replacing Intelligent Key unit.

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   GO TO 2.

2. REPLACE INTELLIGENT KEY UNIT

   1. Replace Intelligent Key unit. Refer to Removal and Installation.

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   GO TO 3.

3. WRITING Nissan Sentra Vehicle SPECIFICATION

   1. CONSULT

      Select “Re/programming, Configuration”. Refer to Work Procedure.

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   GO TO 4.

4. INITIALIZE NATS

   1. Perform NATS initialization.

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   Work End.

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