Support / Fender Jazz Bass Wiring Diagram & Fitting Instructions

Fitting Instructions

The good news is the Jazz Bass is one of the more simple guitars to replace the wiring harness, because the harness is attached to a control plate, which can be removed and worked on with ease.

Removal

Find somewhere safe, dry and secure to place your Jazz Bass guitar while you work on it.
Undo the screws to the control plate.
Carefully lift the control plate up and cut all wires from the body to the control plate closest to the pots. (normally a ground wire or two coloured black)
Cut the pickup wires closest to the pots, leaving the wires as long as possible.
Put the guitar safely out the way for the time being.

Replacement

Working on the control plate, simply remove everything.
At this point you may want to clean the front of control plate where the old pots have been.
You will need to check the size of the holes for the pots and jack socket as on some control plate they are drilled small for cheap electrical components. If they are small, the best way to enlarge them to 10mm to fit CTS pots, is to use a round file.
The control plate is now ready to fit the new harness.
From here everything is in reverse using the wiring diagram below.
Fit the new wiring harness into the control plate.
Solder the 2 x pickup wires to the new volume pots (refer to wiring diagram)
Solder the ground wires to the pots(refer to wiring diagram)
The control plate is now ready to go back into the guitar.
Fit the pickguard back into place, but don’t screw it down yet.

Testing

Plug the guitar into an amp and with something small and metal you should get a response from the pickups by gently tapping the pickup poles/posts. – Or you may have a Multimeter.
If Everything is working, screw the control plate into place.

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