The middle piece is sometime refer to as the PACMAN since it resemble the Pacman character in the game.

The OBD II is basically just for any trouble codes for the engine and evap system. The 20 pins connector will get you into the rest of the BMW specific modules, but you will need to have BMW specific software/scanner to be able to access those modules. Sticking just a generic OBD II connector into that dongle will only read what the OBD II connector can read.

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2006 Infiniti G35
2001 BMW 3.0I E53 X5 Build date 08/2000 SOLD
Lotus Europa 1970 Destroyed by fire
Lotus Europa 1970 S2 Renault Powered
Lotus Type 52 1970 Twincam Webers Powered
PORSCHE 911 Targa 1982 The Garage Queen
Audi Avant donated to Kars for Kids
BMW 525IT Sold
Audi 4000CS Quattro Sold
Jensen Healey Lotus Powered Sold
Opel 1900 Sold
Triumph Spitfire 1971 Sold
Triumph Spitfire 1968 Sold
Plymouth "Cuda" 340 Six pack SOLD