▲ 53 r/Androidheadunits+2 crossposts

What nobody tells you about cheap aftermarket infotainment system retrofit kits.

Official kits are specifically engineered to interface directly with your car’s original CAN-bus system. This ensures complete retention of your vehicle's factory hardware, including:

  • Steering wheel controls: Volume, track skip, and voice command buttons continue to work natively.
  • Factory rotary dials/trackpads: Systems like BMW iDrive, Audi MMI, or Mercedes COMAND retain full knob-based navigation within CarPlay/Android Auto interfaces.
  • Original reverse/360° cameras: official kits switch instantly and automatically to backup cameras or parking sensors without black screens or latency.

And most importantly, because official kits interface directly with CAN-bus system of your car - the Dead Reckoning system is present. Dead Reckoning is a feature that allows navigation apps (Apple Maps, Google Maps, Waze) to continue tracking your position precisely when GPS signals are blocked—such as inside tunnels, multi-level parking garages, or dense urban canyons.

Rather than relying solely on satellite signals, the CarPlay/Android Auto protocol is designed to ingest real-time vehicle telemetry - specifically wheel speed sensors (wheel ticks), gyroscope/yaw rate data, steering angle, and gear selection (forward/reverse).

The presence or absence of Dead Reckoning integration is one of the most significant technical differences between official/OEM retrofits and generic aftermarket solutions.

Decided to post for educational purposes only, because no one seem to know, however it's probably more important for people who own older cars and want CarPlay/Android Auto.
Think about it before deciding to buy some Chinese knockoff retrofit kit for your car. Also if you already have wired CarPlay/Andoid Auto and want wireless - keep in mind that most wireless adapters don't transmit car telemetry, so its going to be using your phone GPS and nothing else.

reddit.com
u/R413 — 4 days ago

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reddit.com
u/R413 — 2 months ago