Service Bulletin

20-021

March 17, 2021

Version 3

Bluetooth® HandsFreeLink® (HFL) Freezes During or After a Call
Supersedes 20-021, dated February 16, 2021, to revise the information highlighted in yellow.
AFFECTED VEHICLES
Year

Model

Trim Level

VIN Range

LX

ALL

Civic 2-door
Civic 4-door

201920

Civic 5-door
REVISION SUMMARY
Under Verifying the Audio Unit Software, the System ucom software version was updated.
SYMPTOM
The HFL system freezes during or after a phone call.
POSSIBLE CAUSE
Some audio units are not updated with the latest software.
CORRECTIVE ACTION
Update the audio unit software.
WARRANTY CLAIM INFORMATION
The normal warranty applies.
Operation
Number

Description

Flat Rate
Time

Defect
Code

Symptom
Code

Template
ID

Failed Part Number

0100A1

Update the audio unit
software.

0.3 hr

03214

03217

A20021A

39171-TBA-A41

Skill Level: Repair Technician

CUSTOMER INFORMATION: The information in this bulletin is intended for use only by skilled technicians who have the proper tools, equipment,
and training to correctly and safely maintain your vehicle. These procedures should not be attempted by “do-it-yourselfers,” and you should not
assume this bulletin applies to your vehicle, or that your vehicle has the condition described. To determine whether this information applies, contact
an authorized Honda automobile dealer.

© 2021 American Honda Motor Co., Inc. – All Rights Reserved

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REPAIR PROCEDURE
Software Update Procedure
1. Connect a fully charged jumper battery to the vehicle, and leave it connected during the entire update procedure to
maintain steady voltage.
2. Open the Honda Firmware Downloader from the shop’s computer.
NOTE: Refer to Job aid Honda Firmware Downloader for more information.
3. Insert a USB flash drive into the computer.
NOTE: Make sure the USB flash drive is empty and is formatted to FAT32.
4. Enter this service bulletin number, the VIN of the vehicle you are working on, and select Search.

5. When the software is found, select the Download icon. Once the download is complete, remove the USB flash drive
and take it back to the vehicle.
NOTE: The software download may take up to 10 to 15 minutes depending on the size of the file and the internet
speed. You do not need to stay with the vehicle during this download.

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6. Turn the ignition to ON.
7. Before updating the software, write down the customer's audio unit presets.
8. First, verify the software information. With the audio turned off, press buttons 1, 3, and 5, then press the VOL/Power
knob on the audio unit in the order shown.

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The Version display screen will appear.

Only update the audio unit software if the software information matches the information shown above and listed
below. If the software information does not match the information shown, no update is needed and continue with
normal system troubleshooting.
NOTICE
Updating the software when the software information does not match what is shown will damage the unit. If that
happens, you will need to replace it.
Software Details

Original Software Version
2019/2020 Civic LX (2dr/4dr/5dr)

System ucom

GA04

HMI ucom

G004

DSP ucom

11C20204

Bluetooth module

HW02-SW03.29.07

9. Press the VOL/Power knob to exit the Version display screen.

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10. Turn off the audio unit, then insert the USB flash drive into the USB port. The audio unit will automatically detect the
USB flash drive and start the update. When the update starts, the screen will go black, the buttons will start blinking,
and the audio unit will beep.
NOTE: If the update does not automatically start, or an error occurs, cycle the ignition to reset the audio unit. Then, go
back to step 9.

11. Once the update is complete, you will hear a long beep, the Honda logo will appear, and the screen will return to the
audio screen.

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Verifying the Audio Unit Software
1. With the audio unit turned off, press buttons 1, 3, and 5, then press the VOL/Power knob on the audio unit in the order
shown.

The Version display screen will appear.

Make sure the software information matches the information shown above and listed below.
Software Details

Original Software Version
2019/2020 Civic LX (2dr/4dr/5dr)

System ucom

GB04

HMI ucom

G004

DSP ucom

11C20204

Bluetooth module

HW02-SW03.29.07

2. Press the VOL/Power knob to exit the Version display screen.
3. Remove the USB flash drive.
4. Set the clock to the correct time.
5. Press and hold the VOL/Power knob to skip the security code screen.
6. Restore the customer’s audio unit presets.
END

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