BMW ICOM diagnostic system has released to the third generation: BMW ICOM A3. ICOM hardware contains 3 parts: BMW ICOM A, ICOM B and ICOM C. With all of BMW ICOM A+B+C parts and software HDD, it is able to diagnose and program BMW Cars, BMW Motorcycle, Rolls-Royce and Mini Cooper.

First of all, let’s explain the function of each part of ICOM.

ICOM A: Main adapter with OBD II connector for MOST (Media Oriented Systems Transport), KCAN, DCAN

ICOM B (MOST interface): additional adapter for optic line, use USB connection with Icom A.

ICOM C (20PIN interface): adapter for old vehicles (before 2000-2001) with round 20-pin connector.

What’s the difference among ICOM, ICOM A1, ICOM A2 and ICOM A3?

1) Appearance.

BMW ICOM and ICOM A1 share the same appearance.
Here is BMW ICOM A2:

BMW ICOM A3 displayed picture below:

2) Software

ICOM and ICOM A1 software are called ISIS (ISTA-P) and ISID (ISTA-D).  Latest version: 2013.01.
ICOM A2 and ICOM A3 software are called ISTA-D ISTA-P (or Rheingold version). ICOM A2 current version: 2015.04 ISTA-D ISTA-P software. ICOM A3 comes with 2015.02 HDD.

3) Firmware/Hardware

BMW ICOM A1 and ICOM A2 share the same firmware. Three firmware version optional: V1.1.8, V1.33 and V1.36. BMW ICOM A3 has the difference firmware/hardware version: V1.37

Here is the free firmware download link for BWM ICOM, ICOM A1 and ICOM A2.(Close antivirus software or set your browser to download success)

ICOM A1 and ICOM A2 firmware PCB board:
ICOM A1 and ICOM A2 firmware PCB board ICOM A1 and ICOM A2 firmware PCB board
4) Function:

BMW ICOM A1 and ICOM A2 share the same function. But due to the old BMW ICOM A module have problem in the cooling and protection design, ICOM A2 adopts the whole aluminum shell body, using aerial explosion-proof connector; and it use the joint connection line which similar to the Mercedes-Benz SDCONNECT COMPACT 4.

And the new ICOM A3 has a higher version firmware which is able to receive a significantly more powerful processor and more storage capacity. A3 comes with robust aluminum box will help to avoid damage in harsh environments when using.

5) Operating system

ICOM can only be installed on Win XP O/S.
ICOM A1: Win XP and Win 7 64 bit O/S
ICOM A2: Win XP and Win 7 O/S
ICOM A3: Professional Win7 64 bit (NO win XP)

In conclusion:

BMW ICOM, ICOM A1, ICOM A2 share the same firmware version and functions but differs in appearance.

The newest version ICOM works better in cooling, runs faster and uses more stable, not easy broken than older ICOM.

ICOM A3 can program all units for all BMW series, but not media.