2018/04/25

GM MDI vs Tech II: MDI wins in running speed & vehicle coverage

I have both clone Tech2 and MDI interface from China. Here, I’ll chip in with my experience and give you some tips if you have a GM and consider buying a tool for it.


MDI/GDS2 is used on C7 Vettes, and other vehicles prior to 2014 (for example, Chev Cruze starting in 2011 uses MDI, as well as others).


I use the Tech2 on my 427 vert as well, and it does everything stand-alone except module recalibration (programming or ‘flashing’).

Btw, There wasn’t a single all-inclusive model year where they cut over from the Tech2 to MDI for all GM models. It had more to do with platforms that were more-or-less fresh designs or clean-sheet designs after about 2008 or so.


Why MDI interface is more preferable for GM:

Flash faster: MDI & GDS2
As for why GM is going to the GM MDI and GDS2, instead of using a Tech II with TIS2000 software, because the MDI with GDS2 flashes a hell of lot faster when you have flash a new module with either it orginal firmware or upgraded firmware. Its also faster to use than having to press buttons on the Tech II for basic commands during diagnostics as well.

Older cars: Tech II & TIS2000
So in regards to the vets, Tech II clone will cover all the C6 cars and older since the last of the updated firmware on the unit covers from here back. If you do need to reflash something, it’s done via Tis2000 with the Tech II as the pass through device.

New & old cars: MDI interface
Since GM did not make upgraded firmware to flash into the Tech II’s to cover these cars like C7, then it’s a MDI that is needed instead. As for the MDI’s firmware, they will cover not only the new cars, but the cars that the old Tech II’s used to cover as well.

Now the glitch on the MDI regarding cloning it, since it has to use the GDS2 software for the pass through only device, GDS2 software has not been cracked like Tis2000 software has been instead.

GM account for subscription: MDI need it
So the only way that even a clone MDI is going to work, is to have a subscription to GM (Few $K a year) to allow you to use the GDS2 software that has to log into GM each time it used instead.

Hence the Clone Tech II unit you get will already be loaded with the most current firmware, and for most of the stuff you going to use the Tech II clone, will just be using the unit by itself without being connected to a laptop.

Also the cracked copy of Tis2000 that you get with the clone model, does not have to be connected/logged into GM to use it for 99% of the stuff (do not need an account with GM).
Note, if push comes to shove and you can not find a copy of the needed firmware to flash into a unit to upgrade a module, then you can get a one day subscription to GM to pull down the needed file from them.

Another place the people have had good luck with as well.

Can I buy a cloned GM MDI interface?


This is for those interested in purchasing a GM MDI from china with software. Here are experience (success and failure) of MDI clone, shared on the MH forum.


Compatibility:

Device works with GDS2 (Opel)
Device works with Tech2Win (Opel, Hammer)
Device not works with SAAB via Tech2Win

GM MDI is working in Consult 3 plus 
gm-mdi-interface

Cars tested- works & cannot work:

1: SAAB 9-5, 2003, 3.0 TID- works
mine is clone from China.
MDI Software 8.1.135.13
GT32
SAAB NAO V9.250
Simply pressed OK when Candy detected and all worked.
Tested on SAAB 9-5, 2003, 3.0 TID

2: 2014 model - works
SAAB NAO V9.250 is from 2014. Already tested.
2003 year too old - not interesting for me.

3: Saab 9-5, 2003, 3.0 - works
Tested by my own, works with Saab 9-5, 2003, 3.0

Online or offline issues:

1: online - good, offline - bad
GM MDI good, interface works online.
update mdi 100%.
offline too bad for new cars.

2: wifi card compatible
at now, chinese clone GM MDI with squ wifi card

3: wifi not working but works good with USB
I bought a cheap one and it only worked with usb. The wired network and wifi did not work. In fact, the card flash socket was missing from the board. Build quality was not to bad. I just use it to flash newer pcm/ecm's.

GM MDI WIFI version:
GM MDI USB version:

Source - a man of his words to trust in:

I would not go by pictures posted on the web as venders share the same photos but the MDI I received from http://www.obdii365.com/wholesale/gm-mdi-multiple-diagnostic-interface.html had a different ethernet connector and missing cardflash socket. It was advertised as (without wifi). It does work fine on USB and for flashing pcm/ecm because at 480 Mbit/s it is almost 5 times faster then ethernet.

The MDI clone works fine with tech2win and also TIS2000. Used it for diags and pcm flashing with no problem (through usb port only)

Credits to all contributors with unbiased reviews in mhhauto.com