I had a minor setback in my project to upgrade my 2004 Mazda RX-8’s in-car navigation capability from the now-ancient factory integrated system. But despite the setback, I have a usable system. Enough to declare this as successful completion of project phase one. By removing the navigation map display unit, and installing a standalone wireless CarPlay/Android Auto receiver in its place, I now experience the following advantages:

• Connects to my Pixel 7 phone via wireless Android Auto, so now my in-car navigation screen has access to up-to-date maps and traffic information.
• Audio entertainment including music or podcasts can stream from my phone.
• User interaction such as setting a destination for navigation can be done via my phone’s highly responsive touchscreen. It’s superior to the sluggish receiver touchscreen and far superior to the factory system of painstakingly typing an address via joystick-controlled on-screen keyboard.

These items were left unchanged, and they were important project criteria:

• Factory appearance with no visible alteration to interior trim. When the car is turned off, the only visible difference is the new receiver has a glossy screen whereas the factory LCD had a matte surface.
• All in-car controls were maintained, including volume control both via center console and steering wheel buttons.

Unfortunately, there were several functional regressions:

• Due to electrical interference, I had to disconnect the factory motor retract mechanism. I’m optimistic I can regain this functionality as a future phase of the project.
• When the factory system loses GPS signal, it can estimate position based on vehicle speed and direction. The new receiver is GPS-only and helpless when signal is lost. I don’t see any way to restore this functionality, but it’s not a high priority to do so.
• The factory system automatically dims the display when headlights are on, and when the light sensor detects low ambient light. The new receiver’s brightness must be manually adjusted. I don’t see any way to restore the headlight response functionality with this receiver. However, buying a different Android Auto receiver with a built-in light sensor may restore auto-dimming capability.

Potential future phases for this project:

• Restore the factory motor retract mechanism. Fortunately, Mazda engineers designed the geartrain to be back drivable. Or in plainer language, I could still adjust the angle manually without damaging either the motor or its gears. This will be important if a headlight or sunlight is inconveniently angled to reflect off that glossy screen into my eyes: I can still reach out to change that angle.
• Install the backup camera that came bundled with the receiver. [UPDATE: completed as phase 2.]
• Install a power switch for times when I don’t want that screen.
• Remove/repurpose other components of the factory navigation system. Including the control panel just behind the shifter, and the map data DVD drive + navigation computer between the rear seats.

For now, I will use the system as-is without the motor retract mechanism. See what other problems crop up during use so I could solve them before going further.