Washburn guitar mg-20 pick up switch position 5 neck pick up no sound or noise humm or anything. all other positions and configurations work?

It's probably 1995 Washburn Lyon WE3, the pickup configuration is two single coil pickups. It would be easier to tell if there was a photo available.

Sounds like you're missing the guitar you paid for. Did you test the pick ups before you left the store or was it delivered? might be a bad weld. The wires might not be making full contact on to the connection of the pick up or the switch.

the switch, has three positions. Typically forward or up will be your neck (or rythm) pick ups, only and will work with one volume knob(usually top right as your looking at guitar), and one tone knob ( top left as your looking at the guitar). when the switch is in the far right or all the way down position, that will be the saddle (or lead) pick-ups. And that works with only one volume knob(bottom right as your looking at the guitar) and the corresponding tone knob. when the switch is in the middle position, botjh volume knobs work and both tone knobs work. You've gotta kinda play around with them to find whatever sound yopur looking for. and tone knobs are very subtle in their changes. good luck

Search this site for one matching your configuration:

http://www.guitarelectronics.com/category/wiring_resources_guitar_wiring_diagrams/

In a guitar with 3 pickups a 5 way switch works like this. With the switch all the way forward( towards the tuning pegs) the pickup closest to the tuning pegs or end of the neck is completely on ( if your volume control is all the way on). The next position (moving away from the tuning pegs or neck) is a combination of the neck pickup and the middle pickup. The third position moving away from the neck is completely the middle pickup. The fourth position is a combination of the middle pickup and the bridge ( where the strings are fastened) and the fifth position is completely the bridge.

if the problem is only on the neck position it would seem that the switch or the pick up wiring is faulty. a little bit of WD40 on the selector switch will sort if the swtch is gone ...if you take the switch out and check the solder on the connections at the rear of the switch you may see the wire loose or solder point faulty.. just a dab with a solder iron should sort here.. you may need to resolder the connection.

Depending on the pick up and switch configuration. You can find most of them at seymourduncan.com and look for your set up. Wether it's two or three pickups and so on. It's almost always standard setup regardless of the brand

Here is their site:http://www.seymourduncan.com/ This site might also help:http://www.gmarts.org/index.php?go=230 You may need a different or new volume control.

sound like a bad audio cord.  Are you too close to the amp and getting feedback?  Do you have the gain up to high?

I don't think this is a valid question for this site.