Mazda CX-30 2024–2026 — technical service bulletin
Bulletin SA-012-26b · NHTSA communication 11032015 · issued Apr 18, 2026
Technical service bulletin
communication type
Electrical System
component
2024–2026
model years
20
vehicle entries
Official summary
Some customers may experience a message "TCU Malfunction. Have the Vehicle Inspected" in the instrument cluster. Additional symptoms that may occur: Connected Vehicle One Time Passcode (OTP) may fail. • Connected Vehicle Remote functions may fail. • The following DTC's may be stored: B1252:87-8B:TCU - COMMUNICATION ERROR WITH CONNECTIVITY MASTER UNIT (CMU) • U0198:00-03:CMU - COMMUNICATION ERROR WITH EMERGENCY CALL UNIT/TELEMATICS COMMUNICATION UNIT REPAIR PROCEDURE 1. Verify the concern. 2. Check if any of the following DTCs are stored: B1252:87-8B:TCU - COMMUNICATION ERROR WITH CONNECTIVITY
Vehicles covered
- 2024 Mazda CX-30
- 2025 Mazda CX-30
- 2026 Mazda CX-30
- 2025 Mazda CX-50
- 2026 Mazda CX-50
- 2025 Mazda CX-50 Hybrid
- 2026 Mazda CX-50 Hybrid
- 2025 Mazda CX-70
- 2026 Mazda CX-70
- 2025 Mazda CX-70 Plug-In Hybrid
- 2026 Mazda CX-70 Plug-In Hybrid
- 2024 Mazda CX-90
- 2025 Mazda CX-90
- 2026 Mazda CX-90
- 2024 Mazda CX-90 Plug-In Hybrid
- 2025 Mazda CX-90 Plug-In Hybrid
- 2026 Mazda CX-90 Plug-In Hybrid
- 2024 Mazda MAZDA3
- 2025 Mazda MAZDA3
- 2026 Mazda MAZDA3
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.