Humbucker signal problem - can you tell me the solution?

S

Shooweri

New member
Hi guys! My friend has a white Hot P-Rails bridge humbucker (SHPR-2B) that doesn't give signal in humbucker mode. The weird thing is that both coils work separately but when wired as a standard humbucker (black hot lead, green+bare to ground) it's completely mute, no signal whatsoever. I've validated this with multimeter and opened up the pickup to see that all wires are connecter where they're supposed to. Pickup hasn't been opened before this and lived a long life in my friends other guitar.

It would be much appreciated if you can help me to overcome this issue. I'm pretty new to pickup repairing but have done other guitar repairs and maintenance for about 6 years. I'm mostly self-taught.

Thanks a lot!
 
Re: Humbucker signal problem - can you tell me the solution?

Are you getting a reading in full mode? This could be a connection between the coils that has broken, but I'd be curious what reading you get on full.
 
Re: Humbucker signal problem - can you tell me the solution?

Mincer said:
Are you getting a reading in full mode? This could be a connection between the coils that has broken, but I'd be curious what reading you get on full.
Click to expand...

Thanks for the fast reply Mincer! The pickup doesn't give any readings in humbucking mode. However, the both coils give reading separately.
 
Re: Humbucker signal problem - can you tell me the solution?

if both coils work separately, then they should work together if wired correctly. you do have the red and white wires soldered together, right? the black and white wires are the for one coil, the green and red for the other
 
Re: Humbucker signal problem - can you tell me the solution?

jeremy said:
if both coils work separately, then they should work together if wired correctly. you do have the red and white wires soldered together, right? the black and white wires are the for one coil, the green and red for the other
Click to expand...

Yup, the pickup is wired with correct color codes. Black is hot output, white/red are soldered together and green/bare are ground.
 
Re: Humbucker signal problem - can you tell me the solution?

but each coil works separately? im not sure how both coils work but they dont work when connected... very odd
 
Re: Humbucker signal problem - can you tell me the solution?

Both coils give normal readings separately, but the humbucker mode won't. I'll try different wiring if that helps and let you know what I find out. Thanks!
 
Re: Humbucker signal problem - can you tell me the solution?

So, I tried every humbucking color combination I know that works with Duncan humbuckers but wasn't able to solve the issue. I tried normal Black-hot/white&red-split/green&bare-ground and reversed black and green wires, as well as white-hot/green&black-split/red&bare-ground and reversed white and red. All combinations give me reading with both coils separately but humbucking mode doesn't work at all. I took the pickup out from my friends guitar about 6 months ago and don't know where it has been stored. It seems to be in perfect visual condition and arrived in it's original box. I also tried every possible DiMarzio color codes just to be sure without success.

Do you guys have any ideas what could be causing this?
 
Re: Humbucker signal problem - can you tell me the solution?

what dcr do you get between the red and green wires? black and white?

how are you trying to wire up the pup? just series or are you using a switch for coil splitting etc?
 
Re: Humbucker signal problem - can you tell me the solution?

When you are measuring, are the conditions exactly identical ( to the last degree) between when its series and measuring the individual coils??

Can you get the same measure on the individual coils (their separate K readings) when the red/white are soldered together. Or do you have to physically desolder this connection to get a reading.
 
Re: Humbucker signal problem - can you tell me the solution?

The readings are: 8,5 between red and green, 13,5 between black and white. I'm wiring it up as a standard humbucker with 3-way lever switch and volume&tone controls. Guitar is Ibanez RGR320 stock pots and upgraded switch. It has Distortion in neck that works fine.
 
Re: Humbucker signal problem - can you tell me the solution?

The problem OBVIOUSLY is NOT with the pup if you are getting readings from each coil. You think you are wiring it correctly, but you aren't.

Is the pup wired into the guitar right now or is it on the bench (out of the guitar)? If it's in the guitar, disconnect the wiring from the switch (you can leave the ground wires, green and plain, connected to the back of a pot). Connect the red and white wires together separate from anything else. Now measure from the ground (green) to the black wire. What reading do you get? Should be somewhere around 22k ohms.

I'm assuming that you got about 22k, because you had to...you got 8.5k with one coil and 13.5k with the other.

So now that we know that the pup is perfect, check how you have it wired. What switch are you using? If you could take some clear pics showing every wire connection I can tell you specifically what to change to give you the results that you want.
 
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Re: Humbucker signal problem - can you tell me the solution?

GuitarDoc said:
The problem OBVIOUSLY is NOT with the pup if you are getting readings from each coil. You think you are wiring it correctly, but you aren't.

Is the pup wired into the guitar right now or is it on the bench (out of the guitar)? If it's in the guitar, disconnect the wiring from the switch (you can leave the ground wires, green and plain, connected to the back of a pot). Connect the red and white wires together separate from anything else. Now measure from the ground (green) to the black wire. What reading do you get? Should be somewhere around 22k ohms.

I'm assuming that you got about 22k, because you had to...you got 8.5k with one coil and 13.5k with the other.

So now that we know that the pup is perfect, check how you have it wired. What switch are you using? If you could take some clear pics showing every wire connection I can tell you specifically what to change to give you the results that you want.
Click to expand...

I took the pickup out of the guitar and I'm troubleshoot the problem using just a multimeter. Both coils give readings as I mentioned but full humbucker mode does not. I've checked that the color codes are correct but it refuses to give ANY reading as a humbucker when black is hot, white&red are soldered together and green&bare are ground. You can find photos below.

Let me know if you need anything else.

Blade coil
blade coil.jpg

P90 coil
P90 coil.jpg

Humbucker mode
hum mode.jpg
 
Re: Humbucker signal problem - can you tell me the solution?

Turn your ohm meter up to 200k when measuring over 20k

Sent from my LM-G710VM using Tapatalk
 
Re: Humbucker signal problem - can you tell me the solution?

at least my sanity is restored :) i couldnt for the life of me figure out how two working coils turned into one non-working pup
 
Re: Humbucker signal problem - can you tell me the solution?

Shooweri said:
Thanks for your help! You've confirmed that I'm complete idiot.

Blasphemy in three, two, one...
View attachment 102812
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I guess I'm an idiot as well because I assumed that if you were using a multimeter you must know how to use it.

Glad you sent those photos, we may never have found out the problem without them. (I guess I'm not such an idiot...at least I did ask for photos).

So just for your future reference (and maybe a few others as well), the multimeter only reads UP TO the setting you have it on. If it is set at 20k it will read up to 20k and in this case where we expected the resistance of the pup to be about 22k, the meter must be turned up to the next higher setting (with this meter it was 200k).

But, don't just indiscriminately set your meter to the highest setting. For best accuracy set it to the lowest setting possible that will include what you are measuring. Did that make sense?

Good catch on that htwheelz67.
 
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Re: Humbucker signal problem - can you tell me the solution?

as soon as I saw the pic I knew, the last time I did that I thought I had 2 bunk BG1400 pickups.....I got the same reading till I turned it up.
 
Re: Humbucker signal problem - can you tell me the solution?

GuitarDoc said:
I guess I'm an idiot as well because I assumed that if you were using a multimeter you must know how to use it.

Glad you sent those photos, we may never have found out the problem without them. (I guess I'm not such an idiot...at least I did ask for photos).

So just for your future reference (and maybe a few others as well), the multimeter only reads UP TO the setting you have it on. If it is set at 20k it will read up to 20k and in this case where we expected the resistance of the pup to be about 22k, the meter must be turned up to the next higher setting (with this meter it was 200k).

But, don't just indiscriminately set your meter to the highest setting. For best accuracy set it to the lowest setting possible that will include what you are measuring. Did that make sense?

Good catch on that htwheelz67.
Click to expand...

Thank you for this. It makes perfect sense! I should've sent photos right away, as it would solved this immediately.

Thank you for your time guys!
 
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