Wiring change from Fender

I recommend checking out this site for wiring schemes

Wiring Diagrams Seymour Duncan Seymour Duncan

The diagram you need is at http://www.dimarzio.com/sites/default/files/diagrams/2h1v2t_3waytoggle.pdf

Need more info: 1- does the volume control still change the level? 2-Does tone control still change the tone? 3- What happens when in the center position on pickup select switch? Put pickup switch in center position (both pickups active). Then take a coin and tap on the pickups. Does bridge pickup sound lower? Lastly remove rear electronics cover and inspect all wiring for something loose or disconnected.

my guess is two positions at one end work(aka 1 and 2, or 4 and 5)? if yes, then 2 of the pickups are wired wrong. (if 1 and 2 work, which are the forward positions, then the middle and bridge pickup are wired wrong, etc.) the problem is there is a variety of 5way switches that are different. i would guess yours is "import" style. are there 8 lugs in a single row on the back of the switch? if yes, you probably have an import switch. best i can do in text is tell you that the middle two lugs are common. this means one goes to the volume pot, and there is probably a little jumper between the two lugs as well. now there are 3 lugs on either side of those 2 common lugs. one set of 3 will probably run to the tone pot in some fashion or be empty. the other set of 3 lugs is for the pickup lead wires. it sounds like at least one or two of those lugs are empty but shouldnt be, or are wired wrong. i cant tell you colors of your wires without seeing it, but this is how it should be, with the exception that the tone knob will probably be on the bottom 3 lugs somewhere. 1 would be the neck pickup, 2 the middle, and 3 the bridge hope this helps, feel free to post a pic of your wiring, etc

I don't know about this specifically, but my general advice is to use the Dimarzio site and forums for info. The bare wire will be ground/earth and the red is hot. It simply goes to here the original one went in the guitar.

My advice is that if you need to ask how to do it, you don't have enough experience to execute this properly and safely. Please take it to an expereinced professional.

Most likely it is wired like most Gibsons. The volume knobs are the two at the neck end, the tones are the two nearest the rear. The lower two are volume and tone for the bridge pickup, the upper two are for neck pickup. Switch down is bridge or lead pickup, switch up is for neck or rythym pickup, and centre position is both pickups one, where all knobs can be used together.

I think this is what you are looking for:http://www.squierguitars.com/pdf/current/Strat/Bullet%20Strat%20with%20tremolo-%20Service.pdf Please let me know if this helps.

The volume is a common problem ... Search for wiring diagrams for your guitar to find a better wiring. Or take it to a guitar repair centre to have it fixed.

To tell which pickups are selected with the switch if it doesn't have the little plate telling you, Turn one volume down and flick the switch one way so you can hear just one pickup.

Two ways of telling which one it is picking up ... A toppy tone is the one nearest the bridge ... a bassy tone is the neck pickup ... The middle selection on the switch is both coils selected ... If you cant tell by tone ... Tap the pick up and you'll soon hear which one you have selected.

The controls should be setup in pairs (as long as the electronics haven't been modified. The two closest to the pickups are the volumes and the other two are the tone controls. The top knob set should be your neck pickup and the bottom set is for the bridge.

Schematics and wiring diagram for the typical les paul (sheraton) controls:
http://www.guitarelectronics.com/product/WDUHH3T2202

Good luck!