Audi RMC: Coding, Adaptation, Datasets

• Figuring out how Audi RMC system is configurable by testing coding, adaptation, datasets, and BAP.
• This type of infotainment unit is poorly documented. I hope this is about to be changed.
• My research is based on a 2012 Audi Q3 equipped with Audi RMC2 non-navigation unit and some parameterization files that I got from community and found over the internet.

How to tell which RMC system I have?

• There are different versions of the RMC system, nav and non-nav, with 6.5" and 7" displays, pre-facelift and facelift.
• Distinguish RMC from MMI: enter Red Engineering Menu and check what's your SW Train. Audi RMC system firmware starts with rmc, MMI starts with bbt, bnav, hnav. Check this: https://youtu.be/R2mUmxFPWBQ
• ~~RMC2 and RMC4~~ RMC and MMI units are using different dataset addresses.
• part # 4G0/8X0 = H5x = RMC2; part # 4G1/8X1 = H6x = RMC4.
• There's also H4x option available. Not sure what it exactly is. Maybe old RMC (RMC1)?
• RMC is usually available at address 0x5F - infotainment. But in some cases at 0x56 - radio.

RMC2 and RMC4 coding

My findings

...both confirmed and anticipated.

• Byte 00
  • bit 0 - Coding confirmation (1=coded)
• Byte 01
  • bit 0 - Steering Wheel (0=LHD; 1=RHD)
• Byte 02
  • bits 0-3 - Car Body (0000=sedan; 0001=avant; 0100=sportback, 0101=allroad; 0110=SUV)
• Byte 03
  • bits 0-1 - Boot screen (00=default; 01=S-Line; 10=S; 11=RS)
• Byte 04
  • bits 0-1 - Car Model (00=A1; 01=A6/A7; 10=Q3)
• Byte 05
  • bit 0 - Air Condition (1=installed)
  • bit 6 - Tire Pressure Monitoring System (1=installed)
  • bit 7 - Ambient Illumination (1=installed)
• Byte 06
  • bit 1 - Parking Sensors (1=installed)
  • bit 2 - Rear View Camera (1=installed)
  • bit 3 - Rain Sensor (1=installed)
  • bit 4 - Central Lock (1=installed)
  • bit 5 - Rear Blind (1=installed)
  • bit 6 - Gear Recommendation / Speed Warning (1=installed)
• Byte 07
  • bit 6 - Comfort Seats (1=installed)
• Byte 08
  • bit 0 - Lane Assist (1=installed)
  • bit 1 - Side Assist (1=installed)
  • bit 3 - Pause Recommendation (1=enabled)
• Byte 09
  • bit 4 - Tow bar (1=installed)
• Byte 12
  • bits 0-1 - Radio Antenna (01=A6/A7 specific; 02=with Sirius; 03=A1/Q3 specific)
• Byte 14
  • bit 0 - Sound System (0=Internal; 1=External)

To investigate

• Byte 05:bit 5 OR Byte 07:bit 5 Something A6 Allroad related (Air Suspension? OR Tilt Display?)
• Byte 08
  • bit 6 - Reverse Seatbelt Tensioner (RGS)? (1=installed)
• Byte 10
  • bit 1 - APS/RVC (1=installed)
  • bit 2 - ??? (0=A1/Q3; 1=A6/A7)
• Byte 11
  • bit 0 - Mic drivers side? (1=installed)
  • bit 1 - Mic passengers side? (1=installed)
• Byte 16
  • bit 0 - Looks like GPS related (100% accuracy in A1/Q3, not so good match in A6/A7)

RMC2 and RMC4 Adaptation

...both confirmed and anticipated.

• 005 - developer mode (0=off; 1=on)
• 009 - bluetooth (0=off; 1=on)
• 023 - display test pattern (0=off; 1=on)
• 034 - Door speaker channel test
• 035 - Voice Command test
• 058 - Speakers test (0=off; 1=on)

RMC and MMI 3G/3G+ Datasets

Audi RMC and MMI 3G/3G+ features and settings (confirmed, anticipated, and unknown).

Checksums

• Last 2 bytes is checksum. It's generated with CRC16-CCITT(FALSE).
• Example: 3 bytes 00 E1 F0 contain value 00 and checksum E1 F0.

Example function activation - parameterization with OBDeleven for Android

• Demo https://youtu.be/jsi80Yr3aoY

RMC Live Data Channels

BAP

• Features available via RMC/MMI interface that are implemented in other modules. Information about those features and some of the settings are send to RMC/MMI via BAP protocol.
• Example: coding for daytime running lights switch is done in module 0x09 but the switch will appear in RMC/MMI menu (which is separate module).

GEM - Green Engineering Menu

Usage

• Requires developer mode to be enabled first (check adaptation above).
• Enter GEM with key combination: [CAR] + [MENU]
• Demo: https://youtu.be/jGcJXQZLzEc

Custom GEM screens

coming soon...

REM - Red Engineering Menu

• Enter REM with key combination: [CAR] + [BACK]
• Demo: https://youtu.be/PRefnQfClug

System reboot

• Enter it with key combination: [BACK] + [Control Wheel] + [Upper-Right]
• Demo: https://youtu.be/KxOsZpEe3cY

Display screenshot

• Make sure there's an SD card inserted and it's not write protected.
• Press and hold buttons [<] and [>].
• Wait for LED confirmation on the control panel.
• Demo: https://youtu.be/ASmqbM54rZk

RMC filesystem access

coming soon...

Credits, Reference, Tools

• Huge thanks to everyone involved in this research!
• Equipment code search engine: http://prsearch.planetvag.com
• Checksum calculator: https://crccalc.com
• RMC2 vw RMC4, optional equipment reserach: https://www.drive2.ru/l/7508336/
• ASCII table: https://www.rapidtables.com/code/text/ascii-table.html
• OBDeleven diagnostic interface (ref link): http://mr-fix.info/redirect/obdeleven