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Mazda CX-30 2019–2021technical service bulletin

Bulletin SA-004-21c · NHTSA communication 10201858 · issued Sep 13, 2021

Technical service bulletin
communication type
Electrical System
component
2019–2021
model years
6
vehicle entries

Official 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: 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 repa

What a TSB means. Technical service bulletins are repair guidance manufacturers send to dealers — they are not recalls, and repairs are not automatically free (warranty extensions are an exception worth checking). The full document is available via NHTSA’s vehicle lookup.