Trying to measure resistance on guitar cable to see if my guitar's pots/pickups are ok

Matt300ZXT

Matt300ZXT

Well-known member
So in trying to diagnose this Warrior I'm having issues with, I'm trying to at least see if my pickups and pots are ok to narrow down a potential issue. The guitar has a HH setup with Duncans, I think it's a JB and 59 but I'm not 100% as it's been a while since I've had them out. I have the red lead on the tip of a cable, and the black lead on the shaft of the cable. The meter is set to kohms.

Bridge: volume on 10, the meter eventually settles around .40-.42 kohms. As soon as I start decreasing the volume, the meter goes haywire with random numbers and some 0L scattered in there, eventually settling at .02 kohms when at 0 volume.

Both pickups: volume on 10, it wants to fluctuate between about .90-1 kohms. When I start decreasing the volume, the meter goes haywire, hits 0L some, then at 0 volume, it stabilizes around .02 kohms.

Neck pickup: volume on 10, it wants to stabilize around .40 kohms. When I start to decrease the volume, it does the same thing as before, and ends up around .02 kohms.

So, aside from getting vastly different readings sometimes between measurements on the exact same settings, and going haywire when I'm turning the volume down, and stabilizing at the same reading when at 0 volume, it seems that the wiring, switch, pickups, and pots all seem to be functioning. It's weird I get zero output from the guitar though into an amp. I'm guessing that something in either the piezo preamp died (yes it has a new battery) or something like that and is somehow killing my output signal, though I don't see how that would do it. I'm considering just removing all the piezo stuff (preamp, battery, extra wiring) and rewiring the guitar to be a traditional 2 hum, 1 vol, 1 tone, 3 way LP style switch and use the 2 micro switches as coil taps, even though I don't really use coiltaps, but might as well use them for something. Then just leaving the blend knob for the piezo system unhooked.

If anyone wants to help me diagnose this thing, I am MORE than happy to take any pictures someone might want and take any measurements with this meter.
 
not completely sure what reading the ohms will accomplish, but I would try setting the meter to ohms and not kohms. also make sure any kind of auto ranging is off if possible. that might keep the readings from jumping around as much.

as far as trouble shooting, I would break it down and test just one pickup at a time, one pot, etc making your way to the output jack to see when or if numbers start looking off to you.
 
Well, I'm reading the ohms to see if there are changes in the signal, meaning the pots or pickups likely aren't the problem with this guitar not having any output to the amp.
 
Read them with Volume on 10. The readings going wonky when reducing volume is normal. Each pickup selected individually should read close it it's DC resistance. The pickup is in parallel with the Volume pot but that should be 500k so it won't reduce the reading by much from the DC resistance of the pickup. When the pickups are in parallel (middle switch position) it should read close to the parallel DC resistance of the pickups.
 
Not exactly sure what all troubleshooting you have done but this is what I have done.

First check your signal path with the meter on continuity. From the pickup out to pot in, then pot out, to selector switch, to jack (or however you have it wired)
Then check every ground, might also be good to draw or look at a chart of how stuff should work.
Last two times I’ve had pickup issues have been with grounding. The first being a poorly soldered ground lug and the second being a ground I forgot to make on some active pickups.
I doubt it’s the pots or pickups. Both should have dc resistance if you disconnect them
 
Check to make sure you took any packaging off the battery. No really. Knew a guy who bought a new 9V that came wrapped in plastic, and somehow forgot to unwrap it before putting it in his guitar.
 
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