Garage Door Wiring
From your description (small as telephone wire) these are bell wires. These are to be used for yor garage door receiver. It runs from the opener to the receiver. For the garage opener you need to connect it to regular house wiring 14awg minimum on a dedicated circuit- black to red and white to white. Did you trace this tan cable to where it goes?
On the back of your opener unit there are 2 or 3 terminals where bell-grade wires are to be attached. On my units (1/2 hp chain drive, with Security+ remotes, and safety sensors) there are 3 terminals. Terminals 1 and 2 are for the opener button you mount in the wall in your garage, so you can open the door when you enter from inside the house. In my manual, these wires are white, and white with red stripe. Is that what you are referring to?
Terminals 2 and 3 are used for the safety sensors, which are mounted at ground level on each side of the garage. These sensors prevent the door from closing if an object is detected. You may not have them if they are not mandated by your state. In Pennsylvania, where I live, they are. Those wires are colored white, and white with black stripe.
Your garage door kit should have a coil of wire colored white/red stripe, and, if sensors are included, 2 sensors, each with coils of wire attached, colored white and white/black stripe. Now, as to what your house has, I‚Äôm not sure. In my experience, homes that came pre-wired for openers only meant that they had the power outlets mounted in the ceilings of the garages, like I previously mentioned. I‚Äôve never known of a house with the controller wire also included since these could vary by manufacturer.
What you may be looking at is additional phone wire or security/alarm wire, but I am not the expert. If your home is brand new, ask your builder to explain. Also, in order to make it worthwhile for you to use them, the wires would have to begin at the location you desire the opener button(s) to be (usually next to the door leading into the house), and end at the ceiling next to where the opener unit is mounted. If you do not have that situation, or you can‚Äôt confirm what those wires are for, it would be best to run the wire supplied with the opener as instructed, and be done with it.
Now, if the wire you are looking at is truly for the opener controls, and not hooked to anything else, simply choose 2 wires to substitute for the white and white/red wires called for in your opener‚Äôs installation manual. Make a note of the colors you use, and hook them up in place of the opener‚Äôs supplied wires as instructed in the manual. I guess it is possible that the wires, since you have 6, may also run to the location where the door sensors are to be located. In that case you should find 2 wires running to each side of the door, 2 to the button location, and all 6 to the opener unit. If that is the case, then draw a little matrix to show which wires in the wall will correspond to the wires described in the manual.
TIP ‚Äìthe sensors are marked ‚Äúsender‚Äù and ‚Äúreceiver‚Äù. If you are installing 2 openers with sensors for 2 separate garage doors, mount the receiver units next to each other between the two garages. In that way, you can, at one glance, tell if there is an obstruction or malfunction in either door (green light is not on), and it keeps the receivers from picking up the beam from the wrong door sender. There are lights on the senders, but they remain on no matter what, unless they loose power.
One last thing: If you do not have power outlets mounted above where your opener(s) are going, then you might need a professional to run the power unless you really, really, really know what to do. Extension cords are not an option if you have to run them down the side of a wall to the nearest receptacle. 110v is not to be taken lightly!
Of course, all this is only based on what you originally posted. If you find anything else which you think may clarify some things more, post it and we‚Äôll try to help, or call the 1-800 number in your door opener installation manual.
Do you have multiple stalls with multiple doors that would later get a separate opener? I don't understand why an installer would put the additional cost into the job of 6 wires vs 2 wire conductor.