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Mazda Connect CMU Hardware Specs (Gen 6 / i.MX6)

The CMU (Connectivity Master Unit) is the computer behind every Gen 6 Mazda Connect head unit. Hardware is by Visteon; the software stack was developed by Johnson Controls (JCI). The same unit shipped across Mazda’s Gen 6 lineup, with source-backed North American v74.00.324A vehicles spanning 2014–2023 depending on model. Its internal designation is MAZDA_GEN_65_CMU (community shorthand: “CMU 150”). For the sourced model-and-year list, see Supported vehicles.

Source basis: component IDs, connector pins, and storage layout are cross-checked against silverchris/mazda-cmu-documentation. SoC capabilities are from NXP i.MX6D product documentation. Firmware-specific names such as MAZDA_GEN_65_CMU, device nodes, and VIP message counts come from local firmware/rootfs analysis.

  • NXP i.MX6D: dual-core ARM Cortex-A9, ARMv7. NXP publishes this family as the i.MX 6Dual application processor line.
  • Clock: 675 MHz (measured at runtime; NXP rates the i.MX6D at up to 1.2 GHz, so the CMU runs downclocked)
  • RAM: 1 GB DDR3 physical, 746 MB Linux-visible; the rest (~258 MB) is reserved for GPU/VPU
  • Secure boot: i.MX6 HABv4 exists in hardware but is not enabled.

This is the constraint that defines the whole platform. Two Cortex-A9 cores at 675 MHz with 746 MB of usable RAM is the budget the entire infotainment stack runs inside, which is why startup time and service count matter so much; see Boot chain and Services.

MediumSizeUse
NAND1 GBRoot filesystem. Datalight FlashFX / relfs FTL.
eMMC (Micron)4 GBUser data, navigation, logs.
SPI-NOR (Macronix)8 MBBootloader, failsafe image, persistent config.

The SPI-NOR holds the bootloader and a failsafe image, which is what makes the unit recoverable after a bad flash; see Boot chain. For the full partition layout, see Filesystem internals.

  • Renesas R5F35MCEJFB: M16C family, 16-bit
  • RTOS: MR30
  • Role: bridges the vehicle CAN and LIN buses to the application SoC

The App SoC talks to the VIP MCU over an SPI bus. The VIP exposes a subset of vehicle CAN IDs to the application processor as read-only telemetry; public documentation confirms its CAN/LIN bridge role. The application side has no direct raw-CAN controller, but selected stock services can ask the VIP-side stack to emit constrained outputs, including navigation guidance toward the cluster/HUD.

  • WiFi: TI WL1285Q (wl12xx driver, SDIO interface)
  • Bluetooth: Murata LBEE6Z2U0C-584
  • u-blox NEO-M8L automotive dead-reckoning receiver
  • High navigation rate (HNR) output up to 30 Hz via sensor fusion (GNSS + gyro + accelerometer + wheel ticks)
  • Hardware documentation also references an STMicro STA8088F, likely a secondary receiver or a variant revision rather than a confirmed second unit on every board.
  • NXP TJA1043 (HS-CAN, bus-selective wake)
  • NXP TJA1042

Two display variants share the same CMU hardware:

VariantSizeResolutionInputNotes
Standard7-inch800×480Resistive touch + commander knobMost models
Widescreen8-inchWider panel, same UIResistive touch + commander knob2016+ CX-9 Touring and up, 2018+ Mazda6, 2020 CX-5 GTR/Signature

Both connect to the CMU over a Maxim MAX9265 serializer link. Standard display part numbers: K123-61-1J0A/B/C (various revisions). The 8.8-inch non-touch widescreen sometimes attributed to these cars is Gen 7 hardware (2019+ Mazda3, CX-30); no Gen 6 car shipped without a touchscreen.