NHTSA ID Number: 10198678
Manufacturer Communication Number: SA-004-21b
TSB/Document Date: 2021-07-02
Summary
When the Telematics Control Unit (TCU) replacement is necessary due to a failure, use MDARS to activate the new TCU after replacement. Use the information in this service alert to initialize the new TCU until the procedure on MGSS is updated. CAUTION: If TCU activation is not performed, connected vehicle functions will not operate. This will have a negative impact on the customer because they will need to return to the dealer for repairs.
BULLETIN NOTES
This service alert supersedes the previously issued service alert listed below. The changes are noted in Red text.
Previous Service Alert
Date(s) Issued:
SA-004/21
05/24/21 and 01/19/21
SA-010/20
06/29/20, 06/01/20, 05/08/20, 04/29/20 and 01/15/20
APPLICABLE MODEL(S)/VINS
2019-2021 Mazda3
2020-2021 CX-30
2021 CX-5
2021 CX-9
DESCRIPTION
When the Telematics Control Unit (TCU) replacement is necessary due to a failure, use MDARS to activate the new TCU
after replacement.
Use the information in this service alert to initialize the new TCU until the procedure on MGSS is updated.
CAUTION:
• DO NOT swap TCU with another vehicle as the TCU is VIN locked after activation. A TCU swap with another
vehicle will disable Connected Services on both vehicles.
• If TCU activation is not performed, connected vehicle functions will not operate. This will have a negative impact
on the customer because they will need to return to the dealer for repairs.
TCU Activation
1. Install the new TCU.
• Mazda3 - TELEMATICS COMMUNICATION UNIT REMOVAL/INSTALLATION
• CX-30 - TELEMATICS COMMUNICATION UNIT REMOVAL/INSTALLATION
2. Use the DCA8000 battery charger SST to maintain battery voltage. Go to SA-034/21.
3. Confirm M-MDS hardware that is in good working condition. Go to SA-066/20.
4. Turn the ignition ON (engine ON or OFF).
5. Connect MDARS to the vehicle.
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6. Select "Tool Box".
7. Select the repair icon.
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8. Select "Mazda
Connect"
9. Select Activating TCU (links
TCU to server) -> "Run".
Wait for "initialization complete"
message.
NOTE: MDARS may show
"Incomplete". This may be
caused by:
• Advanced key is not in the
vehicle.
• Connected vehicle
maintenance mode is
enabled.
• Pacemaker radio wave
interference prevention is
enabled.
• key transmitter power
saving function is enabled.
See SA-040/20.
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10. Select Activating Remote
Control by Smart Phone (links
TCU to BCM) -> "Run".
Wait for "initialization complete"
message.
11. Turn Ignition OFF and wait at
least 2 minutes.
12. Turn Ignition ON and then
check reception strength.
NOTE:
• If DTC U2050:55-TCU (Activation of remote control not implemented) is stored, go to TSB 09-013/20 - DTC
U2050:55 STORED AFTER REPLACING OR REPROGRAMMING TCU.
• If the TCU was not replaced and MDARS shows error code 400t02 and/or ERROR:05, TCU activation was
previously completed. Ignore these errors as TCU activation is not required.
ERROR:05
Error code 400t02
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TSB/Document ID: SA-004-21b
Replacement Service Bulletin Number:
MFR Communication Date: 2021-06-02
MFR Internal Campaign ID/Software Version:
Communication Type: Service Bulletin/Repair Instructions
NHTSA Components: ELECTRICAL SYSTEM
MFR Component System:
MFR Component Subsystem:
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