2021 Nissan Sentra Audio Control Unit Reprogram Campaign

Nissan has initiated Voluntary Service Campaign PM991 (Reference NTB21-066B) for specific 2021 Sentra SV and SR vehicles. This campaign focuses on updating the software for the Audio Control Unit, ensuring optimal performance and addressing any potential issues related to its operation. The 2021 Nissan Sentra Audio Control Unit reprogram is performed at no charge to the customer for parts or labor.

This bulletin, NTB21-066B, is an amendment to previous versions, NTB21-066 and NTB21-066A, published on July 26, 2021, and August 9, 2021, respectively. The latest revision removes battery inspection and replacement steps and updates USB drive information.

What's Being Addressed

This voluntary service campaign involves a software update for the Audio Control Unit in affected 2021 Nissan Sentra SV and SR models. The update ensures the unit is running the latest software version, which may include performance enhancements or bug fixes. Owners of these vehicles will receive this essential software update at no cost.

Important Warnings for Owners

Nissan has issued several critical warnings regarding the 2021 Nissan Sentra Audio Control Unit reprogram:

• USB Drive Usage: Technicians are instructed: "Do not use any other USB drive to perform the procedure in this bulletin." and "The update-software must be the only file on the USB drive." This emphasizes the need for specific tools and procedures.
• During Update: Owners should be aware of the message: "Do not remove the USB drive during the update to the vehicle until instructed to." Removing the USB drive prematurely can lead to issues.
• Unit Damage Risk: A crucial warning states: "Do not remove the USB drive until Figure 15 is displayed. If removed prior to this screen being displayed, the Audio Control Unit may be damaged." This highlights the importance of following the exact steps to prevent damage to the Audio Control Unit.
• Update Conditions: The system will display a message: "To perform a software update, the vehicle must be stopped with the parking brake ON and the engine running. Select a secure location with proper ventilation that may be used for up to an hour. During the update, the system functions will not work. Would you like to start the update now?" This informs owners about the necessary conditions and temporary loss of infotainment functions during the update.

Required Tools and Parts

For technicians to perform the 2021 Nissan Sentra Audio Control Unit reprogram, specific tools are required:

• Special Tool USB Drive: A special tool USB drive, identified as J-52727 (new tool number NI-52727-1), is necessary. This drive is pre-shipped to dealers, and additional drives can be purchased from Tech-Mate.
• Software: The update process utilizes the ASIST software and a CONSULT PC connected to the internet.

Repair Procedure Summary

The 2021 Nissan Sentra Audio Control Unit reprogram involves several key steps performed by a qualified technician:

1. Initial Software Check: The technician first verifies the current software version of the Audio Control Unit. If the version is "321" or "420", the update proceeds. If it's already a newer version, the procedure may not be necessary.
2. Software Download: Using a CONSULT PC and ASIST software, the technician downloads the update software, identified as "PM991_SENTRA", to the special tool USB drive J-52727. This download can take 10-15 minutes.
3. Safe USB Removal: The USB drive is then safely removed from the CONSULT PC following specific steps to prevent data corruption.
4. In-Vehicle Update: The USB drive is inserted into the vehicle's USB media port. The vehicle's engine must be running with the parking brake engaged to maintain battery charge during the update.
5. Confirmation and Installation: The infotainment system will display a message indicating a new software update is available. The technician confirms the update, and the system begins the reprogramming process, which takes approximately 10 minutes.
6. Final Steps: Once the message "The software update is completed. Please restart the system by turning the vehicle OFF and then back ON to confirm the update." appears, the USB drive is removed. The ignition is turned off, the driver's door is opened and closed, and the engine is restarted. The system is allowed to boot up completely.
7. Version Verification: Finally, the technician verifies that the Audio Control Unit's software version has been successfully updated to "423".

Owner Action

If you own a 2021 Nissan Sentra SV or SR, you should contact your authorized Nissan dealer to determine if your vehicle is included in Voluntary Service Campaign PM991. The dealer will check your vehicle's eligibility using Service COMM or Dealer Business Systems (DBS) National Service History. The 2021 Nissan Sentra Audio Control Unit reprogram will be performed at no charge.

Source: NHTSA ID 10218944