Technical
Service Bulletin

Mazda North American Operations
Irvine, CA 92618-2922

Subject:
DTC U2050:55 STORED AFTER REPLACING OR REPROGRAMMING
TCU

Bulletin No.: 09-013/20

Last Issued: 11/17/2020

BULLETIN NOTES
This bulletin supersedes the previously issued bulletin(s) listed below. The changes are noted in Red.

Previously issued TSBs:
Date issued:
09-013/20
10/06/20 and 05/08/20
09-013/20
04/10/20

APPLICABLE MODEL(S)/VINS
2019 Mazda3 vehicles (Japan built) with VINS lower than JM1BP******147656 (produced before June 29,
2019)
2019 Mazda3 vehicles (Mexico built) with VINS lower than 3MZBP******115095 (produced before June 29,
2019)

DESCRIPTION
When the Telematics Communication Unit (TCU) has been replaced or reprogrammed and the software is
updated to ones shown below, DTC U2050:55-TCU (Activation of remote control not implemented) may be
stored in memory with the message “In-Vehicle Network Malfunction” displayed in the multi-information
display.




Japan built vehicles: BDGF-67CK2-B or later suffix.
Mexico built vehicles: BDTS-67CK2-A or later suffix.

NOTE: The Description for DTC U2050:55-TCU will be added to MGSS.
This is caused by a communication error between the TCU, the Connectivity Master Unit (CMU), and the
Body Control Module (BCM) when the control software in them are not of the version being ready for
activation of connected service. To correct this concern, the control software of the TCU, CMU and BCM
have been modified.
When you encounter this concern, reprogram (update) the BCM and the CMU to the latest version.

Page 1 of 5
CONSUMER NOTICE: The information and instructions in this bulletin are intended for use by skilled technicians. Mazda technicians utilize the proper tools/
equipment and take training to correctly and safely maintain Mazda vehicles. These instructions should not be performed by “do-it-yourselfers.” Customers
should not assume this bulletin applies to their vehicle or that their vehicle will develop the described concern. To determine if the information applies,
customers should contact their nearest authorized Mazda dealership. Mazda North American Operations reserves the right to alter the specifications and
contents of this bulletin without obligation or advance notice. All rights reserved. No part of this bulletin may be reproduced in any form or by any means,
electronic or mechanical---including photocopying and recording and the use of any kind of information storage and retrieval system ---without permission in
writing.

© 2020 Mazda North American Operations, U.S.A.
11/17/2020 2:09 PM tlawrenc

Bulletin No.: 09-013/20

Last Issued: 11/17/2020

REPAIR PROCEDURE
1. Update the software version of the CMU to Version 7000C0A-NA01_10050 or later using the MAZDA
CONNECT Update Instructions on MGSS.
2. Reprogram the BCM with the Mazda Modular Diagnostic System (M-MDS) using Mazda Diagnostic And
Repair Software (MDARS) and claim the labor hours according to the warranty information shown below.
NOTE:




If current calibration file name in the ECU FILENAME screen is same as shown below or with later
suffix, reprogramming is not necessary.
[5HB] If the vehicle is applicable to the Mazda Service Program MSP56, performing the MSP56
repair procedure updates the BCM (and LFU) to the modified version.

ECU name
BCM

Body
File name
Japan built 4SD BCKA-66S02-R
Mexico built 4SD BDTS-66S02-M
Japan built 5HB BEMD-66S02-M

3. Perform “Activation Remote Control by Smart Phone”
NOTE:




If this is not performed, DTC U2050:55-TCU and/or U2050:55-BCM will be stored.
This procedure cannot be performed if the key transmitter power saving function is enabled.
SeeSA-040/20.

3a. Connect MDARS.

Page 2 of 5
CONSUMER NOTICE: The information and instructions in this bulletin are intended for use by skilled technicians. Mazda technicians utilize the proper tools/
equipment and take training to correctly and safely maintain Mazda vehicles. These instructions should not be performed by “do-it-yourselfers.” Customers
should not assume this bulletin applies to their vehicle or that their vehicle will develop the described concern. To determine if the information applies,
customers should contact their nearest authorized Mazda dealership. Mazda North American Operations reserves the right to alter the specifications and
contents of this bulletin without obligation or advance notice. All rights reserved. No part of this bulletin may be reproduced in any form or by any means,
electronic or mechanical---including photocopying and recording and the use of any kind of information storage and retrieval system ---without permission in
writing.

© 2020 Mazda North American Operations, U.S.A.
11/17/2020 2:09 PM tlawrenc

Bulletin No.: 09-013/20

Last Issued: 11/17/2020

3b. Select the following:
A. Toolbox
B. Work support icon
C. Mazda Connect
D. Activating Remote
Control by Smart Phone
E. RUN.

NOTE:
1. If TCU is not being replaced, ignore "Complete installation of new TCU"
(a).
2. Battery voltage must be 14-14.5V (b). (see SA-063/20)

3c. Follow the on-screen
instructions.

Page 3 of 5
CONSUMER NOTICE: The information and instructions in this bulletin are intended for use by skilled technicians. Mazda technicians utilize the proper tools/
equipment and take training to correctly and safely maintain Mazda vehicles. These instructions should not be performed by “do-it-yourselfers.” Customers
should not assume this bulletin applies to their vehicle or that their vehicle will develop the described concern. To determine if the information applies,
customers should contact their nearest authorized Mazda dealership. Mazda North American Operations reserves the right to alter the specifications and
contents of this bulletin without obligation or advance notice. All rights reserved. No part of this bulletin may be reproduced in any form or by any means,
electronic or mechanical---including photocopying and recording and the use of any kind of information storage and retrieval system ---without permission in
writing.

© 2020 Mazda North American Operations, U.S.A.
11/17/2020 2:09 PM tlawrenc

Bulletin No.: 09-013/20

Last Issued: 11/17/2020

3d. Select Quick Check (A),
then start the engine and
select the DTC Clear icon
(B).
CAUTION: If the engine is
not started, DTC P2610 is
stored and cannot be
erased.

4. Verify repair.

Page 4 of 5
CONSUMER NOTICE: The information and instructions in this bulletin are intended for use by skilled technicians. Mazda technicians utilize the proper tools/
equipment and take training to correctly and safely maintain Mazda vehicles. These instructions should not be performed by “do-it-yourselfers.” Customers
should not assume this bulletin applies to their vehicle or that their vehicle will develop the described concern. To determine if the information applies,
customers should contact their nearest authorized Mazda dealership. Mazda North American Operations reserves the right to alter the specifications and
contents of this bulletin without obligation or advance notice. All rights reserved. No part of this bulletin may be reproduced in any form or by any means,
electronic or mechanical---including photocopying and recording and the use of any kind of information storage and retrieval system ---without permission in
writing.

© 2020 Mazda North American Operations, U.S.A.
11/17/2020 2:09 PM tlawrenc

Bulletin No.: 09-013/20

Last Issued: 11/17/2020

WARRANTY INFORMATION
NOTE:




If the TCU has been replaced for warranty repair, claim additional hours using the labor operation
number with “BRT” instead of the last three letters “BRX”.
If the TCU has been reprogrammed for warranty repair, claim additional hours using the labor
operation number with “xFT” instead of the last three letters “xFX”.

Additional reprogramming Additional hours
CMU
0.1 Hrs.
BCM
0.1 Hrs.
CMU BCM
0.2 Hrs.

Example:

Replacing TCU
T0524BRX / 0.4 Hrs.
With reprogramming CMU T0524BRT / 0.5 Hrs.
With reprogramming BCM T0524BRT / 0.5 Hrs.
With reprogramming CMU BCM T0524BRT / 0.6 Hrs.

Page 5 of 5
CONSUMER NOTICE: The information and instructions in this bulletin are intended for use by skilled technicians. Mazda technicians utilize the proper tools/
equipment and take training to correctly and safely maintain Mazda vehicles. These instructions should not be performed by “do-it-yourselfers.” Customers
should not assume this bulletin applies to their vehicle or that their vehicle will develop the described concern. To determine if the information applies,
customers should contact their nearest authorized Mazda dealership. Mazda North American Operations reserves the right to alter the specifications and
contents of this bulletin without obligation or advance notice. All rights reserved. No part of this bulletin may be reproduced in any form or by any means,
electronic or mechanical---including photocopying and recording and the use of any kind of information storage and retrieval system ---without permission in
writing.

© 2020 Mazda North American Operations, U.S.A.
11/17/2020 2:09 PM tlawrenc