If your cheap BMW INPA K+CAN USB interface with FTDI chip failed to install drivers or the system prompt cannot locate the drivers. Here is a little write-up on how to fix it.
Disclaimer:
I am using Windows 8.1 system. No sure if it works on yours. You are on your own risk.
Pre-installation caution:
Here are the INPA driver & software free download links. If the driver/software is working, then ignore the next part.
Procedure:
1. Open your Device Manager. Control Panel–Hardware & Sound–Device Manager.
2. Connect the INPA K+DCAN cable with computer/PC-Double click
3. Locate USB Serial Converter->DetailsDropdown Menu->Hardware IDs. The PID number is the one you want. Will most likely be 0000.
4. Download CDM v2.08.30
http://www.ftdichip.com/Drivers/CDM/CDM%20v2.08.30%20for%20Windows%208.1.zip
5. Disable “Driver signature verification” Settings–Change PC Settings–Recovery–Advanced Startup–Restart.
This will restart your PC to Advanced settings. From there: Troubleshoot–Advanced Options–Startup Settings–Restart–F7
Follow these picture guides:
Your PC will then restart with signature verification disabled. You are now able to edit the INPA drivers.
6. Unzip the Drivers file that you just downloaded and open up
7. Open ftdibus.inf
8. Replace every PID_6001 with PID_0000 to match your hardware ID. Scan through the whole document. Then save it.
9. Then find ftdiport.inf. Do the same to ftdiport.inf
10. Back in your Device Manager double click on your OBDII cable again.
Locate USB Serial Convertor Properties->Driver->Update Driver-> Browse my computer.
Locate your driver and install. You will need to install it for both USB Serial Converter and Ports & COM.
11. Setup INPA cable as normal and run INPA software.
It seems that the white FTDI chip INPA cables have to be manually put into D-CAN mode. This file will take care of that. It is normal for the LED to go out.
http://www.mediafire.com/download/35fnrnd3q3dvf3w/D-CAN.exe
If you put the cable into DCAN mode, the LED goes off, and it says there is no adapter connected. Please connect it to the car and run the DCAN mode.