All electric guitars and basses, which are made from wood, are subject to changes in temperature and humidity. These instruments are machines, which have moving parts, and like any other machine, they require periodic maintenance and adjustment in order to insure a maximum level of performance and playability. This is precisely why there are multiple points of adjustment on each instrument. It is very important to familiarize yourself with the different points of adjustment on your guitar or bass i.e. truss-rod, tilt-adjust, saddle height, and intonation, as these features are there for a very important reason.
The woods of your instrument absorb the moisture (humidity) in the air, and expand and contract with changes in both temperature and humidity. This phenomenon may be illustrated easily with the following example: Suppose your instrument is already in tune, and you subsequently transport it during the heat of summer, to an air-conditioned venue. When you take it out of the case and let it cool to room temperature, the pitch of the instrument will dramatically drop as the wood cools and shrinks, causing the tension on the guitar to decrease. While this dramatic example may not require immediate adjustment compensation, it is often necessary to make seasonal adjustments in the action of your instrument to compensate for these changes. It is also important to note that changing string gauges or materials will also affect the amount of tension on the neck and will usually require a neck adjustment to compensate for this change in tension.
It is also, not uncommon that there may be a "settling in" period with a new instrument, where periodic adjustments in the action must be made until the wood stops moving, (bear in mind that seasonal adjustments may still be necessary). If you're a "do it yourselfer", visit our Setup Guides page for detailed information on setting up your instrument.
If you do not feel comfortable making adjustments in the action of your instrument, we would recommend that you have a qualified technician at an Authorized Fender Service Center check out your instrument for the proper setup adjustments approximately every 6 months. This would also be a great time for your tech to keep an eye on such things as such as fret wear, intonation, etc.
Please keep in mind that setups and adjustments are the owner's responsibility and are not covered by warranty.