3.1 Do I need an Interface Adapter?

Yes. The data port in your car is not directly compatible with any standard PC port. The data port in all VW/Audi group cars uses ISO-9141 (K-Lines) and/or CAN bus. You can't just wire up a cable with the appropriate connectors on each end; active circuitry is required. In the case of CAN bus, it's not just electronics either; an "Intelligent" interface containing a microprocessor is the only way a PC can communicate with a car that uses CAN bus for diagnostics. We offer several complete packages consisting of an Interface Adapter, the full-function version of VCDS, at least one free year of updates and full product support starting at $249.

3.2 Can I use an Interface adapter that came with another software package?

The full (non-Lite) version of VCDS is not compatible with 3rd party interfaces at all, even in shareware mode and vehicles that use CAN-Bus diagnostics require a Genuine Ross-Tech CAN-capable Interface. To use the full (non-Lite) version of VCDS, you need to use a genuine KEY- or HEX-, or Micro- series Interface purchased directly from Ross-Tech or from one of our authorized resellers.

If you have an older car which does not require a direct CAN connection for diagnostics (typically cars made before about 2005) you may be able to use VCDS-Lite with a "dumb" ISO-9141 (K-Line) interface. Ross-Tech has not sold interfaces like that since early 2004. In the late 1990's and early 2000's, there were a number of software packages sold which included interface adapters which are compatible with VCDS-Lite. If you can get VCDS-Lite working with one of these, we'd be happy to have you register the software with us for $99. We will then provide support for the functionality of the software -- but not for connection problems.

Most generic "OBD-II" adapters will not work and ones that use ELM chips will definitely not work. If you have some interface adapter of unknown origins, there's generally no harm in trying it, but please keep in mind that Ross-Tech is also not in a position to provide start-up support if you're using any interface adapter that you didn't buy from us or one of our authorized resellers.

3.3 Can I buy an Interface adapter somewhere else?

The full (non-Lite) version of VCDS is not compatible with 3rd party interfaces at all, even in shareware mode and vehicles that use CAN-Bus diagnostics require a Genuine Ross-Tech CAN-capable Interface. To use the full (non-Lite) version of VCDS, you need to use a genuine KEY- or HEX-, or Micro- series Interface purchased directly from Ross-Tech or from one of our authorized resellers.

You may find vendors that are willing to sell interfaces that they claim are "compatible" with older versions of our software like VAG-COM versions 311 or 409. These versions are no longer supported and have been replaced with VCDS-Lite. If you buy an interface from a 3rd party, please do not expect us to provide start-up support. If you can get VCDS-Lite to work to your satisfaction in shareware mode, we'd be happy to have you register the software with us for $99. We will then provide support for the functionality of the software -- but not for connection problems.

Notes: (Caveat Emptor!)

● We've had numerous reports of problems with 3rd-party USB interfaces.VCDS-Lite does not include any USB drivers. In order for a 3rd party USB interface to work at all, the vendor must supply a USB driver for his interface which emulates an RS-232 serial port. This is intrinsically slower than directly accessing the interface via USB. It may also cause difficulties connecting or unreliable sessions with some control modules. If your 3rd-party USB interface uses an FTDI USB UART chip, please download the latest drivers from FTDI; once these are properly installed, make sure that the virtual COM port is configured in the range of COM1 to COM4 and that the latency timer is set to 2 as shown in this screen-shot.

● We've had many reports that certain 3rd-party interfaces (Serial as well as USB) do not work properly with some control modules. If you have a 3rd party interface, please make sure it works with all the control modules in all the cars you're planning to scan before you register.

Again, If you buy someone else's interface and can't get it working, contact the vendor for support! Of course if you buy one of our complete hardware/software kits, we will provide start-up support as well as free updates for at least one year from date of purchase.

3.4 Can I build my own Interface Adapter?

The full (non-Lite) version of VCDS is not compatible with 3rd party interfaces at all, even in shareware mode and vehicles that use CAN-Bus diagnostics require a Genuine Ross-Tech CAN-capable Interface. To use the full (non-Lite) version of VCDS, you need to use a genuine KEY- or HEX-, or Micro- series Interface purchased directly from Ross-Tech or from one of our authorized resellers.

There are a number of websites with plans and schematics for interfaces that claim to work with with older versions of our software like VAG-COM 311 or 409, or with VCDS-Lite.. However, we will not provide links to them, nor do we sell connectors or parts. We do not have the time or inclination to help people debug their home-built interface adapters via e-mail or over the telephone. If you choose to build your own interface,that's fine -- we have no problem with that.Just don't expect any assistance from us until you have VCDS-Lite talking to your car in shareware mode.We have reports that some 3rd party Interface designs do not work correctly with some control modules. If you can get VCDS-Lite to work to your satisfaction in shareware mode, we'd be happy to have you register the software with us for $99. We will then provide support for the functionality of the software -- but not for connection problems. Of course if you buy one of our complete hardware/software kits, we will provide start-up support as well as free updates for at least one year from date of purchase.

3.5 Why does VCDS-Lite require Activation?

All of our Current Interfaces have Activation built-in for VCDS so users never have to worry about Activation.

VCDS-Lite will run through "dumb" interfaces which are not particularly difficult to make and we would like to get paid for our work! The reality is that there are many people in this world who just won't pay for software unless they have to. We've invested a large amount of time and expense in developing this software, and we're trying to make a living with this product. Furthermore, we're trying to sell it at a price that makes it affordable to everyone.The activation scheme is intended to ensure that we get paid by every user, not to make life difficult for registered customers.

3.6 What if I need to run VCDS on more than one PC?

All of our Current Interfaces have licenses for the full (non-Lite) version of VCDS embedded in them. You can download and install VCDS onto as many PC's as you'd like; the full (non-Lite) version of VCDS will read the license from your interface when it connects to a car

VCDS-Lite used with a "dumb" (3rd-party, or obsolete Ross-Tech) interface is licensed for use on a single PC and is not an appropriate solution for people who need to use our software on multiple PCs.

3.7 How do I permanently move VCDS from one PC to another?

All of our Current Interfaces have licenses for the full (non-Lite) version of VCDS embedded in them. You can download and install VCDS onto as many PC's as you'd like; the full (non-Lite) version of VCDS will read the license from your interface when it connects to a car.

If you have a "dumb" interface that does not have built-in Activation see this page: How do I permanently move VCDS-Lite from one PC to another?

3.8 What's the De-Activate button for? Why would I want to do that?

Old versions of our software contained a De-Activate button. This is no longer present in VCDS or VCDS-Lite..

3.9 Why has VCDS become De-Activated on its own?

All of our Current Interfaces have Activation built-in, so the full (non-Lite) version of VCDS should always be Fully Activated once it has been tested on a car. If you have a Current Interface and VCDS has become De-Activated, please contact us.

If you have a "dumb" interface that does not have built-in Activation see this page: Why has VCDS-Lite become De-Activated on its own?

3.10 Can I sell my VCDS System to someone else?

You can sell the Interface, but PC-based activations and support are not transferable.

If you have a "dumb" interface for VCDS-Lite and the purchaser wants the full-function version, he will have to register as a new user for $99.

All of our Current Interfaces act as "dongles" for VCDS, so the software should be fully functional on any PC that meets our requirements. However, we only provide support to the original owner. If you sell your interface to a third party and that person wants to be a "registered user" (eligible for product support and upgrades), he will have to register with us for $99 here.