Classification:

Reference:

DA22-004B

Date:

NTB22-073B

May 10, 2024

REAR AUTOMATIC BRAKING WARNING LIGHT ILLUMINATED
AND/OR DTC C1B56-04 AND/OR C1B56-97 STORED IN THE
ADAS CONTROL UNIT
This bulletin has been amended. See AMENDMENT HISTORY on the last page.
Please discard previous versions of this bulletin.

APPLIED VEHICLES:
APPLIED DATES:

2019-2022 Altima (L34)
Built on or before July 18, 2022

IF YOU CONFIRM
The customer states the rear automatic
braking (RAB) warning light is illuminated,
with “Malfunction See Owner’s Manual”
appearing in the vehicle information display,

AND/OR
DTC C1B56-04 for “SONAR CIRCUIT”
and/or C1B56-97 for “SONAR CIRCUIT” is
stored in the ADAS Control Unit.
Figure 1
ACTION
Reprogram and configure the Sonar Control Unit using the SERVICE PROCEDURE in this
bulletin, if applicable.

IMPORTANT: The purpose of ACTION (above) is to give you a quick idea of the work you
will be performing. You MUST closely follow the entire SERVICE PROCEDURE as it
contains information that is essential to successfully completing this repair.
Bulletins are intended for use by qualified technicians, not 'do-it-yourselfers'. Qualified technicians are
properly trained individuals who have the equipment, tools, safety instruction, and know-how to do a job
properly and safely. NOTE: If you believe that a described condition may apply to a particular vehicle, DO
NOT assume that it does. See your Nissan dealer to determine if this applies to your vehicle.
1/26

SERVICE PROCEDURE
Sonar Control Unit Reprogramming
IMPORTANT: Before starting, make sure:


ASIST on the CONSULT PC has been synchronized (updated) to the current date.



All CONSULT-III plus (C-III plus) software updates (if any) have been installed.



The CONSULT PC is connected to the internet via a cable or Wi-Fi.
o You will be required to enter your username and password during the
procedure.
o If you do not know your username and password, contact your service
manager.



A screen print for warranty documentation can be done from the CONSULT PC
during this service procedure while still connected to the vehicle.



No diagnostic trouble codes (DTCs) are stored.
o Use C-III plus to perform Self Diagnosis for all systems.
o If there are any DTCs, other than C1B56-04 and/or C1B56-97, diagnose,
perform repairs, and erase DTC before continuing.

1.

Connect the Vehicle Interface (VI) to the vehicle.
 Make sure to use the correct VI for the CONSULT.
Make sure the VI is securely connected. If the VI connection is loose during
reprogramming, the process will be interrupted and the control unit may be damaged.

2.

Connect the AC Adapter to the CONSULT PC.
Be sure to connect the AC Adapter. If the CONSULT PC battery voltage drops during
reprogramming, the process will be interrupted and the control unit may be damaged.

3.

Connect a battery maintainer or smart charger set to reflash mode or a similar setting.
To avoid damage to the control unit, ensure a battery maintainer or smart charger is
connected. The battery voltage must be between 12.0V and 13.5V during
reprogramming.

4.

Turn OFF all external Bluetooth® devices (e.g., cell phones, printers, etc.) within
range of the CONSULT PC and the VI.
Make sure to turn OFF all external Bluetooth® devices. If Bluetooth® signal waves are
within range of the CONSULT PC and the VI during reprogramming, reprogramming
may be interrupted and the control unit may be damaged.
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NTB22-073B

5.

Turn the ignition ON with the engine OFF.
To avoid damage to the control unit, the engine must not start or run during the
reprogramming procedure.

6.

Turn OFF all vehicle electrical loads such as exterior lights, interior lights, HVAC,
blower, rear defogger, audio, NAVI, seat heater, steering wheel heater, etc.

7.

Turn ON the hazard warning lamps.

8.

Turn ON the CONSULT PC.

9.

Start C-III plus.

10.

If prompted, select USA/CANADA Dealers from the drop down menu, and then
select OK.

11.

Login using your NNAnet credentials.
IMPORTANT: If not prompted to enter your username and password, the CONSULT
PC may not be connected to Wi-Fi. Close C-III plus, confirm the CONSULT PC is
connected to Wi-Fi, and then reopen C-III plus.

12.

Wait for the VI to be recognized.
 The serial number will display when the VI is recognized.

VI is
recognized

Figure 2

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NTB22-073B

13.

Select Diagnosis (One System).

Figure 3

14.

Select SONAR.

Figure 4

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NTB22-073B

15.

Select ECU Identification.

16.

Confirm the current SOFTWARE # (Figure 5).


If the SOFTWARE # is “L139”, this bulletin does not apply. See the Electronic
Service Manual (ESM) for further diagnostic information.



If the SOFTWARE # is not “L139”, proceed to step 17 on page 6.

28538XXXXX
XXXX

Bulletin does not apply if
this number is “L139”

Figure 5

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NTB22-073B

17.

Select Home.

28538XXXXX
XXXX

Figure 6

18.

Select Re/programming, Configuration.

Figure 7

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NTB22-073B

19.

Use the arrows (if needed) to view and read all precautions.

20.

Check the box confirming the precautions have been read.

21.

Select Next.

Figure 8

22.

Select Automatic Selection(VIN).

Example

Figure 9

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NTB22-073B

23.

Confirm the VIN or Chassis # matches the vehicle’s VIN.

24.

Select Confirm.

XXXXXXXXXXXXXXXXX
XXXXXXXX
XXXXXXXX

Figure 10

25.

Select Confirm.

XXXXXXXXXXXXXXXXX

Figure 11

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NTB22-073B

26.

Select SONAR.

Figure 12

27.

Select Reprogramming.

Figure 13

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NTB22-073B

28.

When you get to the screen shown in Figure 14, confirm that a reprogram is available
as follows:
a. Find the Sonar Control Unit Part Number and write it on the repair order.
HINT: This is the current part number (P/N).

XXXXXXXXXXXXXX

Current Sonar
Control Unit P/N

28538XXXXX
XXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXX

Figure 14

b. Compare the part number you wrote down to the part numbers in Table A.
o If there is a match, continue with the reprogramming procedure.
o If there is not a match in Table A, this bulletin does not apply. See the ESM for
further diagnostic information.

Table A
MODEL

CURRENT SONAR CONTROL UNIT PART NUMBER: 28538-

Altima

6CA2A, 6CA3A, 6CA3B

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NTB22-073B

29.

Select Save.

XXXXXXXXXXXXXX

28538XXXXX
XXXXXXXXXXXXXX
XXXXXXXXXXXXXX
XXXXXXXXXXXXXX

Figure 15

30.

Read the precautions on the CONSULT screen, check the box for Confirmed
Instructions, and then select Next. (Screens not shown.)

31.

Select Next.

28538-XXXXX
28538-XXXXX
XXXXXXXXXXXXXX
XXXXXXXXXXXXXX

Figure 16

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NTB22-073B

HINT: If you get the screen below and it is blank (no reprogramming listed), it means
there is no reprogramming available for this vehicle. Close CONSULT and refer back
to the ESM for further diagnosis.

SONAR

Figure 17

32.

Make sure OK is highlighted green (battery voltage must be between 12.0 and 13.5
Volts).
To avoid damage to the control unit, ensure a battery maintainer or smart charger is
connected. The battery voltage must be between 12.0V and 13.5V during
reprogramming.

33.

Select Next.

Monitor battery
voltage here

Figure 18
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NTB22-073B

34.

Confirm all Judgment items are “OK”, and then select Start.

Monitor battery
voltage here

13.1

Figure 19

35.

Wait for both progress bars to complete (Figure 20).


When the screen in Figure 21 on page 14 displays, the reprogramming is
complete.



If the screen in Figure 21 does not display (indicating that reprogramming did not
complete), refer to Sonar Control Unit Recovery on page 15.

Figure 20
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NTB22-073B

36.

Disconnect the battery maintainer or smart charger from the vehicle.

37.

Select Next.

Figure 21
HINT: Additional steps/operations are required before CONSULT will provide the final
reprogramming confirmation report. Continue with the reprogramming procedure on
page 16.