Car is a 1996 A4 2.8 Quattro. I bought this car used and it came with only 1 key. I have another Key that I had made. I never had a remote to unlock/lock my doors, but searching the forums I have found that If I do have a Keyless entry system i could locate it under my seat in the back seat of the car. I just discovered that I do have this keyless entry system. However, I may need to "Activate" it with my VAG-COM. Can anyone help me with instructions to "Activate" or "Turn-on" this function so that I can get a remote and use this feature? Thanks for all your help in advance.

Well this might be solved already but I can help you.

You don't need vag-com to activate the keyless module under the back seat. Believe it or not it's already set up and working. All you need to do is buy the remote and program it, theres a real simple procedure to do it, you will need 2 keys and the remote, you can search for the procedure or reply to this thread and I'll let you know what its all about.

Make sure you get the right remote control, I have a pic of it posted on the site, search for 96 keyless remote or something similar to see the pic.