Loud hum with humbuckers.

Thundergod

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Back when I just started working on stuff I had the same problem. I didn’t know how to hunt it down, so I simply added an extra ground wire to everything that needed to be grounded. Lol.

you can also solve this with a jumper wire with alligator clips. Again, something was grounded and isn’t anymore. Just find where it’s not and you’re gold.
I used to have a couple of jumper cables with alligator clips. I don't know where they are anymore. I gotta get a couple of them.
 

Tone deaf

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I think Sonar and el84 are on the right track. Something used to be properly grounded and now is not. Your hand touching the metal is closing the ground loop. I agree with Sonar1 that it is likely a bad solder joint. I'd also agree with el84 that the multi-tester is your friend.
 

LeslieFan

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Have you checked the input jack ? Make sure it hasn't loosened up and twisted or something.
 

SteveC

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I have seen this caused by a bad output jack, and I have also seen it caused by a bad switch.

Ohm out the output jack to the back of a pot (or the bridge), then ohm out the switch to the back of a pot (or the bridge).

If it hums with either/both pups, the common links are (among others) the jack and the switch. Either can go bad.
 

Dolebludger

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TG,

From all of the checks you have done, and the fact that you seem to have taken a "vacation" from playing, you might try spraying some contact cleaner into the pup switch. If nothing else, it would do no harm.
 

CerebralGasket

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Plug a known good cable into the output jack of guitar. Measure between the sleeve (ground) of other end of cable to each ground connection in the control cavity (switch, pots, bridge, pups, output jack, etc).

Look for any high resistance readings between those two points.
 

cjpeck

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ahhhhhhh!

A MLP Backstage thread looking for advice about a geetar issue! Even lasted 'till Friday with minimal chicanery from the resident peasants!
The troubleshooting required is in the thread (it's a bad ground somewhere), it only remains for the OP to break out the ol' multimeter and start a-pokin'. Could be that the OP won't believe any of those posts and keep askin' about magic strings that don't bust or what pick will let him bash the crap out of the guitar and not break strings that way.
As for myself, I have high hopes the OP, he seems to not have the ego/anger issues that some of our other regular advice seekers display. We're prolly gonna have to look elsewhere for our Friday Entertainment today...
 

Thundergod

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Thanks for all the replies.

I just tested every metal part and all of them give 0.0 as reading.

Jack is a little dirty, it's a first for any of my guitars. Will clean it up. Still gives a reading of 0.0 either when touching the ground part or through a cable.

The switch shows different readings depending on where I place the terminal, the screws that hold it to the control plate show 0.0, the casing shows no connection. And some parts show varying reading. Pickup contacts on the swirch show 4.76

Tested cables. Ok

Tested the control plate. Ok

There's a screw in the pickguard that reads 0.03 ... I'll take out the pickguard later to check where that's wired.

How do you post pictures here?
 

sonar1

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Thanks for all the replies.

I just tested every metal part and all of them give 0.0 as reading.

Jack is a little dirty, it's a first for any of my guitars. Will clean it up. Still gives a reading of 0.0 either when touching the ground part or through a cable.

The switch shows different readings depending on where I place the terminal, the screws that hold it to the control plate show 0.0, the casing shows no connection. And some parts show varying reading. Pickup contacts on the swirch show 4.76

Tested cables. Ok

Tested the control plate. Ok

There's a screw in the pickguard that reads 0.03 ... I'll take out the pickguard later to check where that's wired.

How do you post pictures here?
Switch and jack sounds suspect.

The little top icon one to the left of the smiling face is for pics
 


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