Fender Jazz Bass - circuit spec & questions

Fran · Post by **Fran** » Sat Aug 28, 2010 11:26 am

My friends usa Jazz Bass has got a few issues, he bought it new 3 years ago but the shop told him its not under any warranty so he wants me to repair it.

First off the neck pickup seems dead, i cant get any reading from it on the multimeter. The bridge pickup is measuring around 4K. This seems low to me?

Secondly the tone pot appears to do nothing. Checking against wiring diagrams it is wired differently, the Hot from the volume goes to the end lug (it goes to the middle on diagrams) then to the jack, it also has two caps; one going to ground as normal and one connected between the Hot lug and the centre lug

The jack is also a stereo jack and not grounded.

He bought this from new so im baffled why it has a pointless stereo jack, and cannot understand what the point is of the second capacitor unless it is to cancel out the tone pot. The dead pickup on a 3 year old expensive guitar is also very strange.

Am i missing something? Im nor familiar with the circuitry but it seems simple yet there are some pointless(?) things going on in there.

Thanks!

robroe · Post by **robroe** » Sat Aug 28, 2010 12:56 pm

simple. shop told him it was new, charged him for a new guitar, when it was used.

either that or someone got ahold of it during its 3 years of life other than the owner, took it all apart and raped the inside of it.

is this some kind of sig jazz bass??

jazz bases don't come with 2 jacks unless you pay some retarded kind of money for a "special model" for an extra 2 dollar jack

Fran · Post by **Fran** » Sat Aug 28, 2010 1:04 pm

It does'nt appear to be a sig model and he says no one has modded it.

My plan is to wire the tone as iy is on the diagrams (remove teh extra cap), ground the jack and replace the neck pup.

Fran · Post by **Fran** » Tue Aug 31, 2010 12:41 pm

I've rewired the tone pot on this thing and that works now, told my mate he needs a new pup as well.
After noticing the serial on this it appears its a Highway One model and judging by reviews a pickup upgrade is essential. Users also seem to often complain about the truss/neck problems but this model seems fine in that department.
God knows what they were doing with that tone pot though, bad day at the office i think.