#1
Hello guys, forgive me if this post seems rather dumb, or if the problem is easy to fix, but this is literally the first time I've ever even had a look inside one of my guitars because of a problem and I could really use some help.

Recently seemingly overnight my Fender Jazz Bass V seemingly just died on me. I plugged it into both my Bass Amp and my Axe FX and got no sound.

Strangely, when plugged into the Axe FX, if I pluck a string my lights on the front indicate that I'm getting an extremely weak signal, but nothing audible. (Before anyone says it, yes, I took off all of the knobs and made sure that they were actually turning)

I went online and looked up the diagram of the wiring for my bass. Apparently, there should be 2 wires connecting to the actual output jack, but on mine there is only one that is connected, I looked around in the cavity and can't find the other wire, and clearly it must have been there at some point otherwise it would have never worked in the first place.

I have included in this thread a picture of the wiring diagram and then 2 pictures of the wiring on my bass. I haven't attempted to mod it in any way, only opened it up to look and compare, I have no experience with soldering anything so I didn't bother trying to fix anything myself yet, I just need some advice.

If you can help me please tell me how or if I should just take it to a shop.





#2
First of all, let me say that here at the Bass Forum, no post that is genuinely seeking advice or assistance is dumb, obvious, or is looked upon with scorn, ridicule, or exasperation. We are here to help anyone who asks for our help. We're kinda cool that way!

Now; on to your bass problem. Since pickups do not simply "die," we can assume that your pickups are fine. About the only way to kill your pickups is to carry your bass through a very powerful magnetic field, such as the metal detectors at airports. So it is going to be some other component that is causing the problem. First, I assume that your bass does not have a battery of any kind. If it does, then if you lose your signal, the first thing to do is change out the battery for a fresh one. That is frequently the culprit with any bass that has active electronics.

The next thing to consider - if you haven't already - is that your cable has shorted out. Try it with another cable, or try the cable you used by plugging it into another instrument. If you get a good signal, then you know that it is not a fried cable.

Since you bass does not seem to have a battery, a sudden loss of signal is usually due to one of two things: a problem with the jack, or a problem with the pickup selector switch. Since your Jazz bass does not have a pickup selector switch, you should focus on the output jack. Output jacks can crap out on you for a number of reasons: a broken wire, a broken spring metal contact lead (the springy metal piece that makes contact with the 1/4" phone plug of your cable), or some sort of buildup of dirt or corrosion inside of the jack that is preventing the signal from going through properly.

The second wire that is connected to the output jack - the one you think is missing - is just a ground wire. It is there. all right. It is that short red-covered wire that is connected to the top of the tone pot by a dab of solder. The diagram you posted just has it connected differently. You can tell that the wire is not missing by the fact that (a.) your bass was working properly before, and (b.) you can see that there is no trace of solder on the other lead from the output jack, which proves that there was never anything soldered to it.

With these facts in mind, I suspect that you are getting a bad connection between the spring metal contact lead of the jack and your guitar cable. Those spring metal contact leads are always the weak link in the design of the output jack. They bend; they break; they get corroded; they just basically suck. If it is the spring metal contact lead on the jack that is malfunctioning, then you will have to replace the jack. Fortunately, jacks are very inexpensive, and if you can handle basic soldering, then you can change out a jack in less than ten minutes. If not, then take it to a good repair technician. A jack swap is not an expensive repair by any means.

From the photographs that you posted, it does not appear as if any of the wiring connections are broken or loose. You would need a multimeter to test each wire, but as I said, they look pretty squared away. I strongly suspect that it is your output jack that has fried. This is truly annoying, but it is just something that we have to live with.

Let us know if this information helps, and good luck with the repairs. Believe me; it is not a serious or expensive problem; whatever the cause.
"Maybe this world is another planet's hell?" - Aldous Huxley
#3
Quote by FatalGear41
First of all, let me say that here at the Bass Forum, no post that is genuinely seeking advice or assistance is dumb, obvious, or is looked upon with scorn, ridicule, or exasperation. We are here to help anyone who asks for our help. We're kinda cool that way!

Now; on to your bass problem. Since pickups do not simply "die," we can assume that your pickups are fine. About the only way to kill your pickups is to carry your bass through a very powerful magnetic field, such as the metal detectors at airports. So it is going to be some other component that is causing the problem. First, I assume that your bass does not have a battery of any kind. If it does, then if you lose your signal, the first thing to do is change out the battery for a fresh one. That is frequently the culprit with any bass that has active electronics.

The next thing to consider - if you haven't already - is that your cable has shorted out. Try it with another cable, or try the cable you used by plugging it into another instrument. If you get a good signal, then you know that it is not a fried cable.

Since you bass does not seem to have a battery, a sudden loss of signal is usually due to one of two things: a problem with the jack, or a problem with the pickup selector switch. Since your Jazz bass does not have a pickup selector switch, you should focus on the output jack. Output jacks can crap out on you for a number of reasons: a broken wire, a broken spring metal contact lead (the springy metal piece that makes contact with the 1/4" phone plug of your cable), or some sort of buildup of dirt or corrosion inside of the jack that is preventing the signal from going through properly.

The second wire that is connected to the output jack - the one you think is missing - is just a ground wire. It is there. all right. It is that short red-covered wire that is connected to the top of the tone pot by a dab of solder. The diagram you posted just has it connected differently. You can tell that the wire is not missing by the fact that (a.) your bass was working properly before, and (b.) you can see that there is no trace of solder on the other lead from the output jack, which proves that there was never anything soldered to it.

With these facts in mind, I suspect that you are getting a bad connection between the spring metal contact lead of the jack and your guitar cable. Those spring metal contact leads are always the weak link in the design of the output jack. They bend; they break; they get corroded; they just basically suck. If it is the spring metal contact lead on the jack that is malfunctioning, then you will have to replace the jack. Fortunately, jacks are very inexpensive, and if you can handle basic soldering, then you can change out a jack in less than ten minutes. If not, then take it to a good repair technician. A jack swap is not an expensive repair by any means.

From the photographs that you posted, it does not appear as if any of the wiring connections are broken or loose. You would need a multimeter to test each wire, but as I said, they look pretty squared away. I strongly suspect that it is your output jack that has fried. This is truly annoying, but it is just something that we have to live with.

Let us know if this information helps, and good luck with the repairs. Believe me; it is not a serious or expensive problem; whatever the cause.


I didn't realize that the connection was grounded. That's good to know as like you said it seems to narrow it down to being the output jack. I've never soldered anything but I've been pretty handy when I need to be so I'm sure after a few minutes I can pick it up and do the job myself. Thank you so much this has really helped me.
#4
Quote by cheosamad
I didn't realize that the connection was grounded. That's good to know as like you said it seems to narrow it down to being the output jack. I've never soldered anything but I've been pretty handy when I need to be so I'm sure after a few minutes I can pick it up and do the job myself. Thank you so much this has really helped me.


Anytime, man! That's what we're here for...when we're not out drinking, that is!
"Maybe this world is another planet's hell?" - Aldous Huxley
#5
Look at it again. There's no ground coming off the output jack at all. The wire and dab of solder you're talking about is the capacitor, there's nothing coming off the ground lug of the jack.

OP if you're not confident/inexperienced with a soldering iron just take it to a job, it will take a tech under a minute to sort it. If you want to give it a crack just solder in a wire from that empty lug and join it on to the solder joint on the top of the pot with the capacitor.
Basses:
Fender Precision Bass
Fender Jazz Bass
1967 Fender Coronado Bass II
Warwick Star Bass
Squier Precision Bass TB
#6
Do you have a multimeter and know a little about how to use it?

Testing pickups and connections is not that hard, if you know a little about it. That looks like a metal plate it's connected to, so the output jack should be grounded by the base of the jack. One thing has been overlooked though. A dirty pot can cause loss of signal too.

Set a multimeter to read Ohms. I think it's the 20,000 ohms setting for pickups, but I'm not familiar with bass pickups. Any ohm range will test continuity though. Higher range will be used for testing the 250K pots.

Touch both leads of the meter together, note the reading, that means solid contact (continuity). Also note what is says when they are not touching, that means no contact. (I'm assuming you know nothing about using a meter, so I'm taking baby steps) Touch one probe to the metal plate, one to the output jack where the wire IS connected. You should get no contact, that means you do not have a direct short. Now try the other connection, which should be ground. It should show you do have continuity (direct contact). That will tell you if you have a bad connection.

Set the meter for the 200,000+ range, try it on both pots, and turn the pots while testing. Impedance reading should go to zero or near zero turned up, full 250K turned all the way down. ( I may have that backward but you should notice a definite change) If that doesn't look right, get some contact cleaner and squirt some inside the pot. Work it all the way up and down a dozen times, plug it in and try it.

Now put a cable in the output jack. I like to use a jack with nothing connected, just a jack so I have just the two contacts to work with, but the other end of a functional guitar cable will work. Check both wires for continuity, between metal plate and jack, only one should show continuity, the ground. And you might want to try it in a working guitar or bass to see how it acts with one that's known to work. That should tell you if you're not getting good contact on the spring tensioner. If that's the case, you can push it inward and re tension it, but it will spring again so go ahead and replace it.

By the way, the only dumb question is the one you don't ask...
Hmmm...I wonder what this button does...
Last edited by Paleo Pete at Apr 3, 2015,