Tom_Strutt Posted April 22, 2011 Share Posted April 22, 2011 My 78 Jazz has just stopped working.. I have a gig tomorrow night which is getting recorded and I ideally want to use it! I opened up the part by jack input and cant see anything lose or wrong and it was literally working 2 hours before I discovered it wasnt working... What can I do? Please help! Quote Link to comment Share on other sites More sharing options...
LawrenceH Posted April 22, 2011 Share Posted April 22, 2011 [quote name='Tom_Strutt' post='1208507' date='Apr 22 2011, 05:50 PM']My 78 Jazz has just stopped working.. I have a gig tomorrow night which is getting recorded and I ideally want to use it! I opened up the part by jack input and cant see anything lose or wrong and it was literally working 2 hours before I discovered it wasnt working... What can I do? Please help![/quote] Do you have a basic multimeter and soldering iron? If so, you'll probably be fine! Either way you need to do some basic fault-finding. First try another lead, and ideally another amp (or into a tuner or something, just so you can confirm you get no signal out). If it's not either of those, unscrew the control plate from the body with the lead plugged in, and check that the tip of the jack is actually engaged with the contact on the socket (ideally, use a multimeter set to resistance (ohms) for continuity test). Also check that the socket is clean at the contact points as corrosion can stop it working, and that there is continuity with the jack sleeve and the socket sleeve. Next, use a multimeter to check the resistance between all the points that are supposed to be connected to earth on the control plate using a standard jazz bass wiring diagram. All the metal bodies of the pots and the jack sleeve should share a common earth with one side of the pickup. If they're all fine then check for shorts to earth/breaks in the + signal wiring (on pickups directly, with volumes down - should be 6-8k each). Quote Link to comment Share on other sites More sharing options...
ikay Posted April 22, 2011 Share Posted April 22, 2011 May sound stupid (probably is) but have you checked your lead..? Unlikely for both pickups or vol pots to fail at exactly the same time so I'd double check continuity of the wiring working back from the jack socket. Quote Link to comment Share on other sites More sharing options...
Big_Stu Posted April 22, 2011 Share Posted April 22, 2011 [quote name='Tom_Strutt' post='1208507' date='Apr 22 2011, 05:50 PM']My 78 Jazz has just stopped working.. I have a gig tomorrow night which is getting recorded and I ideally want to use it! I opened up the part by jack input and cant see anything lose or wrong and it was literally working 2 hours before I discovered it wasnt working... What can I do? Please help![/quote] Have you another lead and amp to check it's definitely the bass? If you're certain that it's the bass, I had a Tele do exactly the same on me last year, it was the jack socket, sometimes the insulation just "goes" and you need a new one. An easy fix if you're half good with a soldering iron, a new jack socket from your nearest Maplins is less than two quid. That's if the bass is dead, ie. no buzzes, completely silent. If you wiggle the jack while it's plugged in do you get noise? If you're getting constant buzzing it could be a pickup wire, could be a dead pot but usually you'd get crackling as you play before that goes altogether. To check for anything other than a jack it may take time, and a circuit tester. Quote Link to comment Share on other sites More sharing options...
Tom_Strutt Posted April 22, 2011 Author Share Posted April 22, 2011 [quote name='Big_Stu' post='1208526' date='Apr 22 2011, 06:25 PM']Have you another lead and amp to check it's definitely the bass? If you're certain that it's the bass, I had a Tele do exactly the same on me last year, it was the jack socket, sometimes the insulation just "goes" and you need a new one. An easy fix if you're half good with a soldering iron, a new jack socket from your nearest Maplins is less than two quid. That's if the bass is dead, ie. no buzzes, completely silent. If you wiggle the jack while it's plugged in do you get noise? If you're getting constant buzzing it could be a pickup wire, could be a dead pot but usually you'd get crackling as you play before that goes altogether. To check for anything other than a jack it may take time, and a circuit tester.[/quote] Checked Amp and Leads. For sure the bass Quote Link to comment Share on other sites More sharing options...
ikay Posted April 22, 2011 Share Posted April 22, 2011 [quote]Checked Amp and Leads. For sure the bass[/quote] The way a jazz is wired, if one of the pups or vol pots fails you'll still get sound from the other. So the most likely culprit is the jack socket itself or the wiring from the jack back to the pups. Use a multimeter to check wiring continuity of all hot (signal) and cold (earth) connections if you have one Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.