GM Bosch Vetronix HP Tech 2 with CANDI

General Motors Repair Technicians use a hand-held computer called the “Tech 2” to diagnose and tune modern vehicles.   It is called the Tech 2 because there was originally a Tech 1, and this is the update.

GM Tech 2

Tech 2

The Tech 2 is like a scan tool on steroids, with some additional tuning options thrown in.  As a scanning tool, the Tech 2 excels.  While an off the shelf scanner will read the Engine Diagnostic Trouble Codes (DTCs), the Tech 2 will read and report information from all the car’s systems, including ABS, Air Conditioning, Air Bags, and other systems a standard scanner will not read.  For example, in my CTS Seat experiment after the seat was replaced the Tech 2 must be used to run a Passenger Presence System relearn.  There is no other way to run this tuning step other than with the Tech 2.  Similarly some vehicle customizations or radio resets require a Tech 2 to perform.

Bosch has this informative video on the Tech 2: Bosch Tech 2 Video

Vetronix made the Tech 1.  The original GM Tech 2 was made by Hewlett Packard and used Vetronix software.  Vetronix purchased the Tech 2 manufacturing rights from HP.  In 2003, Vetronix was acquired by ETAS, a supplier of standardized development and diagnostic tools for electronic control units. In 2006, the Vetronix Aftermarket division merged with Bosch Automotive Aftermarket, responsible for supply, sales and logistics of automotive parts for service of the vehicle.  So today the Tech 2 is ‘made’ by Bosch.

The Tech 2 is used for GM Vehicles from 1992-present.  It is kept up to date by updating the 32  MB Pcmcia memory card with the latest diagnostic software.  Current cars with the CAN bus require the CANDI interface for the Tech II to communicate with the vehicle.

A Tech 2 costs — pick a number.  New models appear to cost as much as $4K, and the retail price is shown as even higher — as much as $8K or $9K depending on the site.  Discount new units are available for as low as $2300 on ebay for example, and used units run a bit less.  There appears to be a market in Chinese clones for the Tech 2 and software, although I am opposed to piracy of intellectual property.  My impression from shopping is that you should budget around $2K for an authentic Tech 2 in good condition with all accessories, 32 MB card, and CANDI module.

In the future GM appears to be moving to a laptop based scanning and diagnostic tool using the GM Multiple Diagnostic Interface (MDI) EL-47955.  The GM MDI will replace the Tech 2 for diagnostics in the future, but will not replace the Tech 2 for 1992-2009 vehicles.

The GM MDI is a compact communication module that manages the transfer of data between a vehicles onboard ECU network and a PC.  The GM MDI offers faster programming speed at a lower cost. Depending on the vehicle architecture, the MDI can be 20%-70% faster than the Tech2.  The GM MDI allows the user to perform Pass-Thru programming procedures using software running on a laptop or desktop PC.   Any PC can be used.

9 thoughts on “GM Bosch Vetronix HP Tech 2 with CANDI

  1. An unfortunate but good place to get them is from Dealers who have closed or mechanics who have retired and are ready to sell. This ad on ebay seems to have a lot of info on the topic and how to tell the difference.

  2. I bought a tech2 after so many frustrations with needing to take the car to the dealer for code checks and system resets… its really crazy that they want so much money for it – it has less smarts that a typical $100 graphing calculator… ridiculous

  3. There are some things one can *only* do with a Tech 2 on some models. In Dec 2012 GM released the final update for the Tech 2, moving now to a Tech2Win application. The Tech2Win application requires a monthly license update, so will be an ongoing expense inconvenient to a hobbyist.

  4. Richard I agree with you the stealer an Gm are robbing Gm customers blind
    if you don’t know anything about your car you are screwed $$$$. I know! but where driving Cadillac’s, They are slowly making it harder and harder for us DIYers to be able to work on our cars! a tech 2 $4,XXX to $8,XXX PISS!! and now they are going MDI????
    I brought a Tech 2 Clone as they would call it and so far it works fine does diagnostic’s and I also reprogramed my ECU with tIS2000 lastest updates which came with a USB dongle key for $5XX so time will tell 🙂 and if im not mistaken aren’t all electronics made in japan and china!!!!!!!

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