Sire jazz bass problem

[alembic1989]

I plugged in my Marcus Miller sire jazz today..haven't played it in a while. Everything is fine except th blend control doesn't work. It only allows sound from the bridge pick up...turned all the way in the opposite direction just cuts out the sound...backing away in the other direction just brings the bridge pick up in. There is no noise from tapping on the pole pieces of the neck pick up. I had a peek under the control plate, and the leads from the neck pick up is hot so the pick seems to be fine...the batteries are fine as the active controls work..I even get a nice hum up to the preamp (following the leads from the neck pick up). I don't understand how this could happen just while it's been sitting on its stand.
Any ideas anyone.
I've even tried squirting contact cleaner into the blend pot...no joy...it wasn't even crackling in the first place.
I'm beginning to suspect the preamp may be faulty.
The pick up btw doesn't even work in passive mode.

Edited July 25, 2017 by alembic1989

[gjones]

If the wires from the pickup to the preamp are live and create a buzz when touched with a screwdriver, then it can only be the solder connections on the pickup itself. I recommend disconnecting them and resoldering them.

[Thunderbird]

I know this sounds silly but try a fresh set of batteries sometimes they can power up things but just don't have quite enough juice to run everything at once so to speak batteries do funny things when left over time

[Woodinblack]

[quote name='alembic1989' timestamp='1501010679' post='3341801']

I'm beginning to suspect the preamp may be faulty.
The pick up btw doesn't even work in passive mode.
[/quote]

In which case it has nothing to do with the preamp. It generally isn't anyway, as the blend tends to work to one input.

For whatever reason the connection between the pickup and the blend control is broken, or the pickup and the ground.