Yamaha Keyboard P-95 sound problem (speakers & headphones)

Hey guys I just got out my psr e343 it’s been in storage for a while everything seems to be working except no sound from internal speakers or aux out jack I have opened it up and had a look to see if I could see any visible damage but can’t see anything just wondering if anyone would have any ideas for me to check cheers scotty
I have a multimeter and soldering iron do I have to remove capacitors to check them and if so does anyone know which ones I would be better off checking cheers
 

MrChips

Joined Oct 2, 2009
20,914
Hey guys I just got out my psr e343 it’s been in storage for a while everything seems to be working except no sound from internal speakers or aux out jack I have opened it up and had a look to see if I could see any visible damage but can’t see anything just wondering if anyone would have any ideas for me to check cheers scotty
I have a multimeter and soldering iron do I have to remove capacitors to check them and if so does anyone know which ones I would be better off checking cheers
You just hijacked this thread. Please stay on your own thread already created.
 
Okay, so C217 & C216 didn’t necessarily help my situation.

The upside is I did a lot cleaner job with the second EC than my first attempt. The third one I chose at random, C408 didn’t go so well. I sorta damaged the board trying to remove the EC.

I’m wondering if I should try to make an attempt at salvaging what’s left of the contact points upon install of the replacement EC... or just take it to a pro PCB repair shop. Also, are there places than can replicate an entire PCB if the installed parts aren’t rare proprietary units? Asking for a friend.
BE3322BD-2DBF-451E-8B1E-29E8219EE26F.jpegE2426F28-D9D6-4544-9257-BCE17C65CB30.jpeg6420D3FD-2302-4D32-A8C4-4FDF88492C4A.jpeg37BE9A90-DB54-4DFF-88E2-A1FA63C3700E.jpeg
 

dl324

Joined Mar 30, 2015
10,536
I sorta damaged the board trying to remove the EC.
Could you call them caps instead of making up your own acronym? I've never heard of an electrolytic cap referred to as an EC.

clipimage.jpg
What technique are you using to remove components that causes this type of damage? The usual method is to remove as much of the solder as possible using a solder sucker, solder wick, or other method. Then break any remaining mechanical connection between the lead and pad. Once all of the leads will move freely, you remove the component.

Since this is on the solder side, I can't think of any reason why part of the pad would lift. Unless you're actually pulling it through the hole with the lead by using brute force.

I recently replaced several caps in a DVR. The holes in the board were so large that when I removed the solder with a solder sucker, the caps fell out on their own.
clipimage.jpg

clipimage.jpg
For components mounted like this, you can cut the leads from the component and remove the leads one at a time. If you pull the lead from the component side while heating the corresponding joint on the solder side, you can remove the lead without damaging the pad. Then you can remelt the solder and use a wet toothpick to clear the hole. If you decide to remove excess solder after doing this, be careful. The pads and traces are held in place by glue that will release if too much heat is applied to the copper. If you apply any mechanical force, do it in a direction that won't lift the pad. Refer to the red arrows in the picture below:
clipimage.jpg

What is the diameter of your iron tip, and temperature?
No luck after C408. I'll keep plugging away until I find the culprit.
Most capacitors will fail open (after likely having an initial internal short). In those cases, you can tack a known good capacitor in parallel with the bad one and see if it helps. If it does, then you can remove and replace the bad one.

If the cap failed short, this technique won't work.
 
Last edited:
Thanks for the advice, I don't know the size or temperature of my iron, its a pretty basic plug and play from Radio Shack.

I've just been gently dabbing the joint with heat to melt the solder and gently pulling the component from the other side, after solder-sucking the joint to begin with. I learned my lesson with C217 but I then I go and overdo it and melted the glue underneath. Wish they sold these caps at Walmart or Target because my local mom and pop shops are either shutdown or out of stock.

I also had no idea these tools existed to repair PCBs...
 

dl324

Joined Mar 30, 2015
10,536
I also had no idea these tools existed to repair PCBs...
My advice is to not use them. They cost $15-25 and will dry out quickly once they're opened. I have two dried up tubes of that stuff and used each one once. You can't solder traces made from them.

You can repair damaged boards by replacing pads, through holes, and traces. But the best method is to avoid the damage in the first place.

I use adhesive backed copper tape. They make some specifically targeted to electronics, but it's much cheaper if you use copper tape intended for stained glass windows or slug barriers. I "borrowed" my Wife's roll of half inch tape and cut it down to what I need. You use a burnishing tool to make it adhere to the board.

Wish they sold these caps at Walmart or Target because my local mom and pop shops are either shutdown or out of stock.
Join the club. I get almost all of my parts through mail order. There's a surplus store about 15 miles from me (about the distance I drive to buy groceries because I live in a rural area), but their prices aren't very good. I just plan ahead as much as possible and always buy extras. When I needed to replace 3 caps in my DVR, I bought 20-30 of them.
 

dl324

Joined Mar 30, 2015
10,536
I don't know the size or temperature of my iron, its a pretty basic plug and play from Radio Shack.
If you plan on doing more soldering, do yourself a favor and buy a decent iron.

I bought one of these on eBay last year for $32:
clipimage.jpg

It's a backup for the W-TCP I've had since the late 70's. The heating element burned out and I decided to buy a couple of backup irons when I replaced the heater so I won't be without an iron again. I also bought a WTC202 for $51. The irons were a bargain since the replacement element alone was $22.

Prices were from 16 months ago. They've probably gone up since then.

The temperature on these irons is controlled by the tips which come in 600/700/800F.
clipimage.jpg
I use a PTP7 for just about everything. Been using the same tip since the late 70's.
 

serifpersia

Joined May 19, 2020
9
So in order to find the bad caps all I have to do is test each capacitor's continuity? As I said I tried the jump wire on 6 and 5 but sadly the relay closes after 2-3 seconds so those might be good. (C216, C217)
 

dl324

Joined Mar 30, 2015
10,536
So in order to find the bad caps all I have to do is test each capacitor's continuity?
That's not a reliable way to test a capacitor in-circuit. The meter will charge the capacitor at a rate that depends on what the capacitor is connected to. That will be a poor way to isolate a defective capacitor.

A better way to check capacitors without removing them is to use an oscilloscope. If the capacitors are for power supply filtering or signal coupling, you can see if they're working as expected.

What people have been doing to date could be classified as guessing.
 

Jetronic

Joined May 26, 2020
4
So in order to find the bad caps all I have to do is test each capacitor's continuity? As I said I tried the jump wire on 6 and 5 but sadly the relay closes after 2-3 seconds so those might be good. (C216, C217)
I have the exact same problem as serifpersia with the P95 and try jumping pins 6 and 5 but still no sound. Appreciate any advise on next steps to troubleshoot the issue. I have a soldering gun and multimeter bought from Radio Shack some 35 ago and rarely use it. It's still working. I have high school knowledge of electronics with college electives.
 

serifpersia

Joined May 19, 2020
9
I have the exact same problem as serifpersia with the P95 and try jumping pins 6 and 5 but still no sound. Appreciate any advise on next steps to troubleshoot the issue. I have a soldering gun and multimeter bought from Radio Shack some 35 ago and rarely use it. It's still working. I have high school knowledge of electronics with college electives.
Do you hear the relay closing when you insert a headphones in? I just bought a pair of headphones and when I plug them in I hear a relay closing sound and when I remove it I hear the same thing. Sadly no sound comes out of the P-95.
 
I have the exact same problem as serifpersia with the P95 and try jumping pins 6 and 5 but still no sound. Appreciate any advise on next steps to troubleshoot the issue. I have a soldering gun and multimeter bought from Radio Shack some 35 ago and rarely use it. It's still working. I have high school knowledge of electronics with college electives.
So as user dl324 showed us, a basic understanding of electronics and simple tools can be a great help to everyone in this forum. I've been trained on electronics and even this scenario has kinda humbled me into approaching a more skilled set of hands on the circuit board. If it weren't for this forum, we'd all be SOL and even after trying and failing to repair it myself like so many lucky others here i had to seek help IRL. What we do know about this common issue we have is that replacing every one of the electrolytic capacitors may be the safest course of action... and eating the $50 to have someone who does this stuff out of their garage for fun like I did may be the quickest method of getting a working P95 again since its almost a relic at this point lol
 

serifpersia

Joined May 19, 2020
9
So as user dl324 showed us, a basic understanding of electronics and simple tools can be a great help to everyone in this forum. I've been trained on electronics and even this scenario has kinda humbled me into approaching a more skilled set of hands on the circuit board. If it weren't for this forum, we'd all be SOL and even after trying and failing to repair it myself like so many lucky others here i had to seek help IRL. What we do know about this common issue we have is that replacing every one of the electrolytic capacitors may be the safest course of action... and eating the $50 to have someone who does this stuff out of their garage for fun like I did may be the quickest method of getting a working P95 again since its almost a relic at this point lol
I'm using it as a midi controller but I really wanna hear the piano samples. But I read online that some stuff like pianoteq which I have sound better than those samples. But at the same time I heard the p95 on youtube and I like the way it sounds. Its not really urgent but it would be nice to get a fix for it.
 
I forget sometimes I could probably just plug it in and MIDI it...

I just got my PCB back and it didn’t solve the issue thus far, so next we’ll replace the LC4625 component
 

Jetronic

Joined May 26, 2020
4
Do you hear the relay closing when you insert a headphones in? I just bought a pair of headphones and when I plug them in I hear a relay closing sound and when I remove it I hear the same thing. Sadly no sound comes out of the P-95.
Yes, I hear the relay clicking when I insert headphone or removing it. If I short pins 5 and 6 on connector to the HP board I hear the clicking after about 2 seconds of power on. Again, no sound from either the headphone or speakers when any key is pressed. I wonder if I remove capacitors C216 and C217 in the AM board would make any difference in troubleshooting.
 

Jetronic

Joined May 26, 2020
4
Yes, I hear the relay clicking when I insert headphone or removing it. If I short pins 5 and 6 on connector to the HP board I hear the clicking after about 2 seconds of power on. Again, no sound from either the headphone or speakers when any key is pressed. I wonder if I remove capacitors C216 and C217 in the AM board would make any difference in troubleshooting.
After reading original comments by GermanCoca it appears my P95 has a slightly different issue in that there is no sound even if I disconnect the HP board from the AM board and there is still no sound on any key through the speakers or headphones, only the relay clicking sounds.
 

serifpersia

Joined May 19, 2020
9
Yes, I hear the relay clicking when I insert headphone or removing it. If I short pins 5 and 6 on connector to the HP board I hear the clicking after about 2 seconds of power on. Again, no sound from either the headphone or speakers when any key is pressed. I wonder if I remove capacitors C216 and C217 in the AM board would make any difference in troubleshooting.
I'm certain that we have the same problem. Same symptoms here relay clicks after power on even with the jump wire. Plugging and unplugging headphones results in the relay clicking. If you find a solution let me know. I won't open mine anytime soon
Where did u place the jump wire? Did you place it in the HP side connector or on the AM side? I placed in the AM side of the connector and I unplugged the cable on the HP board. Which way is the correct one? I read that you have to do it on the AM side not on the HP side. Can you post a picture of how that looks maybe I did it wrong.
 
Last edited:

Jetronic

Joined May 26, 2020
4
I put the jump wire on the HP side. It has the numbers 1 and 6 printed next to the connector. It appears more than two of the the 16v 100uF capacitors are likely the cause of the problem as solved by member none2k in this thread so I plan to replace C112, C216,C217, C404 and C408 on the AM board. I will update when I receive the parts and done switching.
 
Top