Squier is a Fender-owned musical instrument company. Squier manufactures budget versions of Fender guitars including the Stratocaster and Telecaster guitar, as well some original instruments. The Squier Telecaster is typically fitted with cheaper stock pickups than the Fender Telecaster, and as a result you may choose to upgrade your pickups to improve the guitar's tone. The pickup layout of Squier's Telecaster varies between models. Some have two single coil pickups or two humbuckers and others have a humbucker pickup at the neck position and a single coil at the bridge. The wiring layout depends on the pickup configuration.
Obtain a detailed wiring schematic for your specific model. Squier's website has an archive of wiring schematics. Select your model from the list. The wiring diagram will illustrate how the pickups are connected to the potentiometers and output jack. This is essential information if you plan to upgrade the pickups.
Set up a suitable work space. You need sufficient room to layout the guitar down flat, with good lighting, ventilation and access to a power source for your soldering iron.
Remove the strings. To get access the wiring you need to remove the pickups. To do this you need to take off all of the strings.
Unscrew the existing pickups. Whether you are upgrading your pickups or just fixing the wiring in your guitar, you need to remove the pickups. Loosen and remove the screws holding the pickups in place and gently remove the pickups from their cavity. They will be attached to the wires, so do not yank them.
Disconnect the wiring from the back of the pickups. Use a soldering iron to melt the connection and set the pickup to one side.
Remove the back plates. This enables you to access the potentiometers and terminals to which the wires are soldered.
Disconnect the wiring that connects the pickups to the volume potentiometer. Your new pickups come with fitted wires, so it is easier to use that wiring. You can leave the wires that run from the pickup selector toggle to the potentiometers and the potentiometers to the output jack in tact if you wish, or you can remove it and replace it with new wire.
Slide the wire from your new pickups through the gap in the pickup cavity so it enters the pickup selector cavity. Gently pull it through at the other side and solder it to the correct terminal on the pickup selector switch. The wiring schematic will illustrate exactly which terminal to connect it to, but you usually connect the red wire to the terminal closest to the pickup in question. Then solder the black wire to the volume potentiometer terminal to complete the wiring circuit. If you disconnected the wiring between the potentiometers and output jack, reattach that wire as per the schematic.
Screw in the new pickups and test the guitar. If there is a crackling sound, check for loose connections. If there is no sound, double check that you've followed Squier's diagram.
Use a shaving brush to remove solder particles once you've melted the connections.
Only solder in a well ventilated area.