Only the subwoofer, front right, and front left speakers work. Is there a setting that I can adjust to turn the other 3 speakers on? Only 3 of the 6 speakers show up on the display.

go to audio set up and configure the system for 5.1 or higher sound output.then only all the speakers ll work

Hello,
In a surround sound system, the correct way to listen to music is in stereo mode which will play out of your left and right channels and your subwoofer. When viewing a movie with surround sound, then you should use your rear speakers. The key element to remember is that rear speakers are only intended to play your sound effects, and will not play full range audio. Thats what your fronts and center are for. If you simply want to override this, than you will need to select the direct sound field on your receiver and than it will send full range audio to all speakers connected. Most likely, its not going to sound that good. If you dont know what each sound field does, here is a list and function of the most commonly used ones.
Stereo-Front Left and Right speakers including subwoofer
Dolby Digital or PLII Movie-these are the bost options for your surround sound
Direct-All speakers connected get full range signal
Good Luck

Every stereo has it's intricacies, once you learn the controls then you can adjust the sound. if you have adjusted the balance to equal, then you may have a broken by door swing ground or positive, sometimes the ohms are split by a common positive connection (front and rear) contained with in the circuit of left or right. This crappy circuit could kill 3 of your 4 speakers, but then with the addition of an after market sub, who knows what kind of monkey business has been committed. Start from scratch in stead of chasing down electrical gremlins. Run new wires to all the speakers, dump the sub. Rebuild what should be there in the first place. Verify manufacturers connections and your interpretation of said, in the harness. Verify that the radio or amp can handle a sub without some goofy mono marriage of rear channels to obtain required ohms for crappy walmart sub Bazooka.

On second thought go to best buy, apply for credit card, and tell them that you want to bump down the road.

You mean the right and left satellite speakers are working but the subwoofer is not. Try to adjust the bass control of the subwoofer at the back. Set it to full.

easy to check out bro get some power to your tuner give it half volume even if its just radio static -adjust the fader to the front only and plug the speaker leads into the different colored wire groups -one group at a time -if i remember correctly there should be 4 color groups white/white-black and grey/grey-black should be your front left/right and green set should be rear along with a purple but if you arent sure then do like i said and just fade to the front and hook up a speaker to each color group -the 2 groups that work now- are your front leads-you can then determine left from right by adjusting the balance.label your leads with some tape and a marker for next time and good luck

First of all you should never indicate speakers as Large unless they can produce below 20Hz (which is very low), otherwise always set your speakers to Small.

Second, did you also indicate in teh setupmenu that you have a subwoofer? Because if all speakers are set to Large some receivers will omit a subwoofer because Large indicates the speakers can reproduce all sounds even below 20Hz.

So walk through your setup menu, say YES when the sub (SFW) is asked for and that should do the trick.

Sounds like the rear volume is just turned down. Cant be the amp if the front and subs are working

This may be in the sound card settings itself. Even though you may have adjusted the Windows settings {if thats what your using} the sound card needs to also be set up for surround. Some sound cards do not support 4 speakers or surround sound systems. Go to Device Manager and find your sound card and manufacture then check there technical support page for info.