I fried something while soldering in my Les Paul...NEED HELP!

[TCW]

Hi All,

After fixing a loose soldering joint on my Les Paul (grounding the bridge pickup sleeve to the outside of the volume pot - CTS 500k) my bridge PU no longer worked. The neck PU worked fine and when the middle position was selected there was sill a different sounding signal.

Thinking I fried the volume pot, I installed another one. Still the same problem, except no signal in the middle position!

Any idea what's going on? Could I have fried something else besides the volume pot?

Thanks!
Tom

 

[Zerberus]

Re: I fried something while soldering in my Les Paul...NEED HELP!

^^ you could have fried the insulation inside the pickup hookup wire, causing a short... assuming it`s vintage style wire and not 4 conductor

 

[TCW]

Re: I fried something while soldering in my Les Paul...NEED HELP!

^^ you could have fried the insulation inside the pickup hookup wire, causing a short... assuming it`s vintage style wire and not 4 conductor

Yea, it's a vintage style. Great. How do I check?

 

[Zerberus]

Re: I fried something while soldering in my Les Paul...NEED HELP!

Hook up a multimeter to both the braid and the conducter while unsoldered from the pot, and see how much it reads in Kiloohms... if it reads significantly less than 7 kiloohms (lowest known value for any humbucker as I have no Idea what`s in there now) or the reading jumps heavily (multiple kiloohms) you`ve probably got a short and need to shorten the wire..

 

[TCW]

Re: I fried something while soldering in my Les Paul...NEED HELP!

Hook up a multimeter to both the braid and the conducter while unsoldered from the pot, and see how much it reads in Kiloohms... if it reads significantly less than 7 kiloohms (lowest known value for any humbucker as I have no Idea what`s in there now) or the reading jumps heavily (multiple kiloohms) you`ve probably got a short and need to shorten the wire..

Thanks! I give it a try. FYI, it's an SH-1 in the bridge.

Tom

 

[Zerberus]

Re: I fried something while soldering in my Les Paul...NEED HELP!

then 7k is just about perfect for "lowest possible value"

 

[DrNewcenstein]

Re: I fried something while soldering in my Les Paul...NEED HELP!

I was gonna say a bad toggle switch, or maybe the wire that connects those pots to the switch?

 

[TCW]

Re: I fried something while soldering in my Les Paul...NEED HELP!

Well, I ran the test with the multimeter. It read 8.6 mOhm (after jumping around a little). I tried cutting a couple inches of length and re-soldering anyway. No dice.

I either fried the pot AGAIN or there's something going on with the switch. :flush:

 

[Wonker]

Re: I fried something while soldering in my Les Paul...NEED HELP!

Test the pot use your DMM

If it's a 250K pot it should read 250K ohms then go down to 0 ohms smoothly. If it's a 500K it's the same.

 

[TCW]

Re: I fried something while soldering in my Les Paul...NEED HELP!

Test the pot use your DMM

If it's a 250K pot it should read 250K ohms then go down to 0 ohms smoothly. If it's a 500K it's the same.

Cool. Where are the test points for red and black?

Thanks.

 

[Wonker]

Re: I fried something while soldering in my Les Paul...NEED HELP!

If the solder points are pointing up it's the left and middle I think. Turn the pot and you should see the Ohms go up or down on your DMM.

You can just see the over all value of the pot by doing the two end points also.

This is just off the top of my head I could be wrong and it is late.

Remember when testing resistance/ohms you need to have what your testing powered down and isolated from the rest of your circuit.

 

[TCW]

Re: I fried something while soldering in my Les Paul...NEED HELP!

Oh, one more thing...

When I have the bridge PU all the way down, the middle position puts out a signal (but a little noisy), but when the bridge vol is turned up again, the signal is gone.

Not sure what this means for the 3-way switch.

 

[DrNewcenstein]

Re: I fried something while soldering in my Les Paul...NEED HELP!

You've got 2 volumes and 2 tones, right? And each pickup goes to its own pair of Volume and Tone knobs?

The knobs run to the switch. Check the wire that goes from the bridge Volume/Tone to the switch. You may have cooked the wire when doing the first soldering job.

Easy way to test this is to reverse the bridge and pickup connections - put the bridge on the Vol/Tone for the neck and vise-versa.