Guitar Wiring help needed

nowuckenfurries

My bottom humbucker has stopped working, when I select it using the switch all I get is a high pitched whine, no other sound from the pick up at all. (EDIT the lower pickup works when the 3-way switch is in the middle position... ie both pickups working @ the same time)

I've opened the back of the guitar & there is a wire coming from the back casing of the volume pot going no where... i.e one end is soldered to the pot & the other end is not attached to anything!

I've looked around the rest of the wiring module & can not see any places where the wire could have been soldered.

Any help or advice would be appreciated!!

Eoin Madsen

Any chance of a clearer picture?

The pot casing/back should be grounded. If one of the pots is no longer grounded it would explain why the corresponding pickup only works properly when both pots are in the signal path.

nowuckenfurries

Clearer picture attached 15072008191.jpg The wire is coming off the pot on the left, where should the bare end be attached to?

Cheers:)

spoonbadger

What kind of wiring setup is this? one volume,one tone and 2 buckers?

I'll see what i can dig up for ya.

spoonbadger

Actually,just looking at it, it looks kinda like it's a loose ground. The loose wire, is it just soldered onto the top of the pot?.

nowuckenfurries

spoonbadger wrote: »

What kind of wiring setup is this? one volume,one tone and 2 buckers?

I'll see what i can dig up for ya.

Yes 1 volume, 1 Tone & 2 humbuckers..

spoonbadger wrote: »

Actually,just looking at it, it looks kinda like it's a loose ground. The loose wire, is it just soldered onto the top of the pot?.

Yes its just soldered to the top of the pot along with the other black wires

cheers:)

spoonbadger

hmmm.It's a ground wire alright....

...now,this wont sound very technical at all.....

....but i want you to turn on your amp, select your bottom 'bucker, play a chord....

....and touch the bare wire to the casing of the *other* pot....

....and tell me what happens

Wazdakka

spoonbadger wrote: »

hmmm.It's a ground wire alright....

...now,this wont sound very technical at all.....

....but i want you to turn on your amp, select your bottom 'bucker, play a chord....

....and touch the bare wire to the casing of the *other* pot....

....and tell me what happens

ohplease ohplease ohplease let something blow up..

Bet It'd sound awesome

spoonbadger

Wazdakka wrote: »

ohplease ohplease ohplease let something blow up..

Bet It'd sound awesome

"Now i just turn it on,and get this bit,and touch it here and...."

*BOOOOM!*

"....That was awesome "

Ya see furry hater,it looks like a ground wire that came loose. From what i can see, it seems that ground wire attaches to the other ground wire on the second pot (see the black wire connected to the shell of pot 2?).

If this doesnt work i'll see what else i can do for ya, but i'm almost certain thats the problem.

nowuckenfurries

Touched the wire off the other pot, no explosions:D ... in fact nothing at all:(

edit: should this wire be going into the body of the guitar fron the pot ( there is anotherwire from the *other pot* going into the body of the guitar along with the red & yellow wires) see pic

spoonbadger

Yes! Yes it should.But unforuntately i couldnt see any hole for it in the pic (still cant. needz better cameraz )

Yup,it should go into the boy and should probably connect to the bridge with the other 2 wires. I'm not sure where/how it connects to the bridge, but thats where it's supposed to go.

Where does that hole lead to,do you know?

EDIT: actually no,that might not be a ground wire at all. That may be the wires leading to the pickups (more likely actually).

Try taking out the pickups and see if one of them is missing a wire,or has an exposed patch of solder.To be honest,that could be the problem too.

nowuckenfurries

spoonbadger wrote: »

Yes! Yes it should.But unforuntately i couldnt see any hole for it in the pic (still cant. needz better cameraz )

Yup,it should go into the boy and should probably connect to the bridge with the other 2 wires. I'm not sure where/how it connects to the bridge, but thats where it's supposed to go.

Where does that hole lead to,do you know?

EDIT: actually no,that might not be a ground wire at all. That may be the wires leading to the pickups (more likely actually).

Try taking out the pickups and see if one of them is missing a wire,or has an exposed patch of solder.To be honest,that could be the problem too.

Right, I've taken the strings off & removed the pick-ups... there are 2 pickup wires, Yellow to neck pickup & Red to the Bridge pickup (both pickups picture) both pickups.jpg

If you look at picture "pickup 1" you will see the *other* black cable comming into the pickup bay & returning back out.... to the bridge I presume pickup1.jpg

There are no black wires attached to any of the pickups, just the yellow & Red wires...... So i'm still baffled as to where the "stray" black wire goes to.....

Also I've noticed that if i plug the guitar to the amp, the top pickup will work ok, the second will only work when I move the toggle switch to the middle position & then goes dead when I move it to the bottom position...... BUT if i reverse the switch order, i.e. start in the pottom position & move to the middle, the bottom pickup stays dead......

wiring bay.jpg


Does anyone else have one of these Thomann Harley Benton SG's (HBS200BC) that would be able to have a peek into the wiring & maybe take a picture & post it here also for a comparison???

andyl222

Plug the guitar in and select your bridge pickup, you say it emits a squealing sound yeah? now get a screw driver or anything at hand and tap the pickup, see if the tapping is amplified. Just need to establish if the pickup is in fact creating a signal, or is dead. It could be an internal prob in the pickup. First things first, find out if the pick up is sending a signal.

nowuckenfurries

Cheers Andy,
The "Squeeling sound" has stopped anyway. (prob just feedback from the amp to start with earlier today)

The bridge pickup will only work when the 3-way selector is moved from top pickup position to the middle position, there both pickups work (tapped them etc). But when the switch is moved to the bridge position there is nothing, dead as a dodo...

68 lost souls

It seems to me to be a grounding issue. I cant erally tell from the pictures but is there a ground going from the pot to the pickup selector?

There should be a place where all the grounds meet and one wire from that to the output jack where is this point?

Johnny Storm

nowuckenfurries wrote: »

The bridge pickup will only work when the 3-way selector is moved from top pickup position to the middle position, there both pickups work (tapped them etc). But when the switch is moved to the bridge position there is nothing, dead as a dodo...

Dodgy switch, possibly?

68 lost souls

I was thinking about this last night when I went to bed and thought possibley the switch too but then there is still an issue with the loose wire. I mean its not like it is supposed to go to no where?

Eoin Madsen

The black wire coming through the cavity is the bridge ground.

The white coated wires coming out of the red and yellow pickup leads are the signal wires for the two pickups - these are connected to either side the of the switch. The centre of the pickup selector switch is connected to the volume pot. Also coming from each of the red and yellow leads should be a ground wire. It's unclear from the picture but these may simply be a coax type sheath or a thin uninsulated wire. There's a black ground wire which seems to end up somewhere under the switch that I assume is to earth one or both of these pickup grounds. I'm guessing the loose black wire is also meant to connect to something down there in a similar fashion, and consequently one of the pickup circuits is currently broken when it's own its own.

68 lost souls

68 lost souls wrote: »

It seems to me to be a grounding issue. I cant erally tell from the pictures but is there a ground going from the pot to the pickup selector?

There should be a place where all the grounds meet and one wire from that to the output jack where is this point?

Kinda what I was getting at with that. Eoin explained it better though. It seems to me. That is missing a ground but not sure. Maybe clip it on with crocodile clips or something and test it.

nowuckenfurries

The black wire coming through the cavity is the bridge ground. Thanks for identifying that one for me!
The white coated wires coming out of the red and yellow pickup leads are the signal wires for the two pickups - these are connected to either side the of the switch.

The centre of the pickup selector switch is connected to the volume pot. Also coming from each of the red and yellow leads should be a ground wire. It's unclear from the picture but these may simply be a coax type sheath or a thin uninsulated wire. These are uninsulated wires as red & yellow are dual core, ie bare wire & white wire inside


There's a black ground wire which seems to end up somewhere under the switch that I assume is to earth one or both of these pickup grounds. This black wire goes to the volume pot casing

I'm guessing the loose black wire is also meant to connect to something down there in a similar fashion, and consequently one of the pickup circuits is currently broken when it's own its own. I have touched the "Loose" wire to every contact point in the wiring bay to no avail

Here is the wiring bay again without the cable tie in place 16072008197.jpg

68 lost souls

Is there a foil on the back of the cavity cover? It could possibly be the grounding coming from that.

nowuckenfurries

68 lost souls wrote: »

Is there a foil on the back of the cavity cover? It could possibly be the grounding coming from that.

After a lot of googling!! It is in fact the sole purpose of this wire!!! Halilulah!!!

Johnny Storm wrote: »

Dodgy switch, possibly?

I've borrowed a multi tester from a mate & tried the switch & yes the switch is faulty in the lower position & further examination + very careful listening the switch does go click, click, ping (where it should go click!!)

Cheers folks for all your help with this one, hopefully Thomann can send a replacement switch or take the guitar back for repair under warranty (expires in 2 days!)

This has certainly been an education regarding the internal workings of an electric guitar to me !! :D:D


68 lost souls, I hope you didn't loose too much sleep!! :eek:


Thanks again Folks!!

NFW

68 lost souls

Glad we could help. I knew there was an explanation for it. No didnt loose sleep. I have an unhealthy obsession with the workings of guitars anyway.

Hopefully they can sort it out for you on the warranty. The shielding ground is one of the first things i should have thought of but im more familiar with front cavities and its not an issue with them since the connection between the pot casing and the pickguard connect it to earth anyway where as on the rear covers there is no direct contact between it and any other part.

The combination of two faults is what threw me cause the shielding ground should have little or no impact on the pickup problem. Oh well. You learn from this kinda thing.

Good luck getting it sorted man.