Volume pot does nothing until the very end

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I just wired a previously-working pickguard and pickups into a new Strat build, transplanting it whole. I changed nothing in the wiring apart from running on two new wires to the jack socket. Now the volume does nothing until the very last part of its travel. 

I must have wired something up wrong. What’s most likely? I wired the jack cup backwards? Thats the easiest to fix, because I have to take the neck off to remove the pickguard.

Extra info:

The bridge pickup is wired into the middle pickup’s tone control (it controls both). 
The gitar has a treble bleed mod added (not by me)
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Comments

  • Also, there is no hum. So maybe I wired the other end to the wrong lug on the volume pot...
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  • SporkySporky Frets: 27568
    By "does nothing" do you mean it's full volume until turned very low, or no volume until its turned very high?
    "[Sporky] brings a certain vibe and dignity to the forum."
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  • Full volume until it gets the the bottom, then all the volume goes at once.

    Playing with it a bit more, it seems that the top end — tone-wise — is reduced slightly as I turn it down.  
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  • ICBMICBM Frets: 71950
    The two non-grounded terminals on the volume pot are shorted together. Either there's a whisker of wire or solder bridging the gap, or the treble pass cap has shorted by being overheated.

    "Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski

    "Just because I don't care, doesn't mean I don't understand." - Homer Simpson

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  • Nice. It could be either. The wires are very short so the soldering was a bit like keyhole surgery. I’ll check it now. 
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  • Could it be the soldered joints in the switch shorting out on the copper shielding? The donor Strat wasn’t shielded under the switch. 
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  • Ok. The multimeter doesn’t show continuity across the resistor/cap, so I guess that means they’re not shorted. The joint looks clean. No hairs, no shorts that I can see. 

    Anything else?
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  • ICBMICBM Frets: 71950
    It may not be a complete short that would show up on a continuity test - if it's an overheated cap it could be a few hundred ohms or so, which would still do the same thing to the signal.

    That is the definite cause of the symptom you're describing though.

    "Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski

    "Just because I don't care, doesn't mean I don't understand." - Homer Simpson

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  • I disassembled everything, and thought I’d found a few hairs at the other end of the wire. I’ve put everything back together, but it still doesn’t sound right. I guess I’ll try to pick up some a new cap over the weekend. Perhaps removing the treble bleed is a good idea, to eliminate that.

    Another symptom is that the guitar sounds muddy, even into a Princeton reverb. 

    Damn, strats are a pain to work on. I can’t believe you have to remove the neck to get into it. 

    Thanks for for the help. I never would have found that on my own. 
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  • Fuck it. I’m going to clip the cap and resistor and do the 50s mod. I prefer it anyway. 
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  • Update: I just got out of the guitar’s innards. I removed the cap and resistor across the volume pot, and re-wired it with 50s wiring, like in the diagram.

    Problem fixed, and the guitar is actually improved. I prefer this wiring in general, but I thought I'd leave the existing treble bleed in place out of laziness.  

    Thanks again for the diagnosis, @ICBM ;
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  • thegummythegummy Frets: 4389

    Damn, strats are a pain to work on. I can’t believe you have to remove the neck to get into it. 
    What do you mean by this?

    It's a total pain on my fender bass that the neck has to come off to adjust the truss rod but on any Strat I've seen, there's never been a need to take the neck off to access the pickguard or electronics.
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  • thegummy said:

    Damn, strats are a pain to work on. I can’t believe you have to remove the neck to get into it. 
    What do you mean by this?

    It's a total pain on my fender bass that the neck has to come off to adjust the truss rod but on any Strat I've seen, there's never been a need to take the neck off to access the pickguard or electronics.
    The pickguard is tucked quite far under the neck, so you either have to remove the neck, or all the strings, to remove it. The body has individual single-coil routes, so you can’t slide it down like you could with bigger routes. 
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  • thegummythegummy Frets: 4389
    thegummy said:

    Damn, strats are a pain to work on. I can’t believe you have to remove the neck to get into it. 
    What do you mean by this?

    It's a total pain on my fender bass that the neck has to come off to adjust the truss rod but on any Strat I've seen, there's never been a need to take the neck off to access the pickguard or electronics.
    The pickguard is tucked quite far under the neck, so you either have to remove the neck, or all the strings, to remove it. The body has individual single-coil routes, so you can’t slide it down like you could with bigger routes. 
    Ah I get you. I always remove and change the strings but I can see that if you remove the neck you can keep the strings on and save buying a new set. Never thought of that!
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  • ICBMICBM Frets: 71950
    edited January 2018
    Some models don’t have enough clearance in the rout to slide the pickguard out from under the 22nd-fret extension - the early Highway 1 was like this, I can’t remember if it’s been changed, I haven't worked on a later one for a while. It’s a real pain, you have to take the neck off or at least loosen the bolts so you can tilt it up a lot.

    "Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski

    "Just because I don't care, doesn't mean I don't understand." - Homer Simpson

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  • thegummy said:
    thegummy said:

    Damn, strats are a pain to work on. I can’t believe you have to remove the neck to get into it. 
    What do you mean by this?

    It's a total pain on my fender bass that the neck has to come off to adjust the truss rod but on any Strat I've seen, there's never been a need to take the neck off to access the pickguard or electronics.
    The pickguard is tucked quite far under the neck, so you either have to remove the neck, or all the strings, to remove it. The body has individual single-coil routes, so you can’t slide it down like you could with bigger routes. 
    Ah I get you. I always remove and change the strings but I can see that if you remove the neck you can keep the strings on and save buying a new set. Never thought of that!
    If it was normal mods and maintenance, I’d wait until changing the strings. On. New build like this though, I’m opening up the bonnet so often it would get expensive and wasteful. The locking tuners really help, though. 
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