Now here is an alternate wiring method for the Precision Bass (P-Bass), or any other bass which has a split pickup (G&L, Squire, Ibanez, etc.) This method has the sensors in parallel wiring mode.
This wiring method shown is for passive sensors. NOTE: You may be able to do this with active sensors, but you need to get power to the sensor.
This method (passive parallel wiring) will give your bass a “brighter sound”. You may also notice that the output of the bass is weaker, and this is because you have cut your sensor impedance in half with this method.
Note: that the sensors are wired this time in parallel, not in series. This method has some benefits, and some drawbacks too. You may wish to install a Double Pole Double Throw (DPDT) switch, in order to change this wiring configuration to the standard series_wiring on the fly while playing.