Intermittent PC3 dilemma

[Bif_]

Our church has a PC3, purchased used some years ago. It began having intermittent issues getting stuck on bootup. After jostling it around, it would start working again.

 

After some time of dealing with this, I contacted American Music and Sound (Kurz's distributor) and after several emails I was left with the impression that they would likely not be able to repair it.

 

After continuing to deal with the problem for a while I finally took it to a local Kurzweil service center. I was told they resoldered something and it worked flawlessly for well over a year.

 

The problem returned, we took it back to the same service center and was told they couldn't find the source of the problem.

 

It has gotten worse and now requires raising the instrument up on one side and dropping it onto the stand from about 3-4 inches. It will normally work again for weeks after doing this. (I know, this sounds pretty stupid.)

 

I know I could fix a cold/bad solder joint (and that's what this sounds like to me). But trying to figure it out seems overwhelming.

 

Throw in the towel and replace it?

[J Graul]

I had the same problem. It would hang up on boot on some screens. I had to hit it a few times to get it to come up. Then it would hang up in the middle of gigs. Frustrating!! Turns out it just needed to be cleaned really well. Working like a champ now.

[Bif_]

I had the same problem. It would hang up on boot on some screens. I had to hit it a few times to get it to come up. Then it would hang up in the middle of gigs. Frustrating!! Turns out it just needed to be cleaned really well. Working like a champ now.

 

What was cleaned? (Keybed, pitch/mod wheel, buttons on front panel?) That would make sense as I know you're not supposed to touch anything during bootup.

[MoodyBluesKeys]

In many cases, cleaning the Molex plugin connectors with a good contact cleaner (NOT WD40) will restore operation. Start with the ones that can be reached by removing the small access panel on the back. That only takes a couple of minutes.

Taking off the whole back is a bit more effort, if needed. The PC3 is built like a clam shell. Remove the side pieces first (hint - there is a screw under the side piece that must be removed, then the little tang pulled out, as it holds the top of the side piece on)

Do not remove the inner screws on the back, only those at the edges. The inner ones hold the keybed in place. Be careful in opening, and document exactly where cables pass through little cutouts in the metal pieces, it is possible to short a cable when putting back together.

After separating any of the plugs, be very SURE that you plug them back in so that the pins match. On some, it is possible to get them off, this can be fatal to the electronics.

Even more likely if dropping the unit 3" restores it.

[Meta]

A PC3 will fail to boot if a control is erroneously sending data even when it's not being moved (or if you move a control during bootup). It can seem like an intermittent problem because a faulty control may only exhibit that behavior if it happens to be in a particular position during bootup.

 

Jean Robert Bellefeuille sent me the following tips when I had a PC361 boot problem. He's Kurzweil's Manager of Technical & Customer Support:

 

"1) update the OS to the latest, v2.21. Update available below (installation instructions included):

 

http://kurzweil.com/product/pc361/downloads/

 

2) run scanner diagnostics:

 

Remove all external connections except power. Power up. From any functioning mode, press 456 on the numeric keypad simultaneously. This will activate "scanner diagnostics" . It takes a few seconds to load completely - you will see a variety of LED flashes and text displayed on screen. Wait until the first two rows are filled in and the 2nd row reads:

 

"Press "CANC" + "ENTER" to Exit Diagnostic

 

This screen displays front panel activity - move a slider, press a button etc, the display confirms what you do. In this case, begin by setting all of the sliders (including Master Volume) to zero. Mod wheel too. Pull the pitch wheel all the way down as well.

 

Then move each control, one at a time, away from "zero" and see if any continue to generate data even when you are not moving them. None should. But sort of like a data mousetrap, we are looking to see what may still be outputting when it should not be and thus have a better idea of what specifically needs repair. this test is just an attempt at making any service easier/faster by helping possibly identify things up front."

 

 

For my Kurz, it was slider #9. In case of a failed boot, moving that slider slightly and rebooting allowed the next boot to succeed. That would be a less destructive workaround than dropping the keyboard, if the problem is actually triggered by a slider being in a certain position or range.

 

Hope that helps.

 

 

[Stokely]

I have had a flickering screen for a couple years now on my pc3. I tap it, it usually goes away for a long while. That was the only problem, right up until a particular gig where it wouldn't reboot--it would boot, but into any one of 4-5 states, generally with some degree of "hieroglyphs" on the screen.

 

So glad I had a second board, and that gig cemented my feeling of "have a backup for everything!"

 

I had a guy check it out, he's owned and worked on various Kurzweil boards...he couldn't find any issues.

 

Anyway, before he checked it I was going to completely reset it in "safe mode" (whatever it is called), then I noticed a boot option. I figured, why not give it a try. It booted up normally and hasn't had any issues booting since then.

 

The tech guy recommended selling it--he said sooner or later the screen is going to fail on Kurzweils, his thoughts not mine--but I don't feel right doing so, at least not at a price that is worth it for me to sell. I paid less than 900 on it used, looks pretty mint, so I figure I'll continue to gig it until the horse dies on me

[Sven Golly]

As soon as you realize that the Kurzweil is a dedicated computer, and that it does a POST (Power On Self-Test) when you turn it on, and it behaves exactly as your PC will if you're sitting on the QWERTY keyboard when you turn it on, you'll be better.

 

I had an issue with a couple of dirty faders that were sending out spurious data on their own. I 'fixed' the issue at the gig by moving all faders through the full range of motion and then leaving them in the middle of the range before turning on the power. Worked every time.

 

Took it into get it serviced/cleaned, works beautifully.

 

Also, if you're abusing your gear (tossing it into a soft case and then putting stuff on top of it) you're risking damaging faders/buttons, which will also result in the boot issues.

[Delaware Dave]

"..A PC3 will fail to boot if a control is erroneously sending data even when it's not being moved .... during bootup...

From the firmware version 2.10 release notes:

"..GENERAL:

 

Fixes/Improvements:

 

Boot-up with 'noisy' continuous controllers (be it user interaction or faulty controller) could freeze the boot up process. Fixed. .."

 

I would open up the user access panel on the bottom of the keyboard and reseat all connectors. My guess is that one of the connectors is causing the issue. It is possible that the connector has to be reseated inside the keyboard as well which means you will need to open up the keyboard.

 

I would try the user panel connectors first. Takes 10 minutes to do; then if you still have issues then go the harder route of reseating the internal connectors. Do a google search on youtube, and "kurzweil pc3 disassembly". Several videos to show you how to take the beast apart correctly. I'm confident this is your issue; while you're in their reseating the connectors you might as well clean them with a deoxit type product so that the contacts are clean.

[Sven Golly]

"..A PC3 will fail to boot if a control is erroneously sending data even when it's not being moved .... during bootup...

From the firmware version 2.10 release notes:

"..GENERAL:

 

Fixes/Improvements:

 

Boot-up with 'noisy' continuous controllers (be it user interaction or faulty controller) could freeze the boot up process. Fixed. .."

 

Yep, but given this quote:

 

requires raising the instrument up on one side and dropping it onto the stand from about 3-4 inches.

 

I wasn't going to assume that they'd done a firmware update on it, as they're too busy bouncing it off the stand.

[Al Coda]

...

I had an issue with a couple of dirty faders that were sending out spurious data on their own. I 'fixed' the issue at the gig by moving all faders through the full range of motion and then leaving them in the middle of the range before turning on the power. Worked every time.

 

Took it into get it serviced/cleaned, works beautifully.

 

YESS !

 

My experience ...

The faders are better than the pitch-wheel and modulation wheel pots are.

The original ALPHA 10k pots aren´t sealed unfortunately.

I had "pitch wheel center position" issues as well as mod wheel transmitting random values when not in use.

Replacing both pots by SEALED (!!!) ALPS pots (used by Yamaha) did the trick.

 

Then MIDI CC fader E showed issues ...

 

The faders of my PC361 just only needed a simple clean job.

Compressed air and some minimal dose (!) of Vaseline spray made my now over 6 years old PC361 work like a champ again.

 

Removing the fader board before doing that clean job might be a good idea.

We did it that way.

 

A.C.

 

[Delaware Dave]

I wasn't going to assume that they'd done a firmware update on it, as they're too busy bouncing it off the stand.

lol

[Bif_]

Many thanks for all the helpful suggestions. Looks like all is not lost. I'll report back with my findings.

 

You guys are great.

[Bif_]

I wasn't going to assume that they'd done a firmware update on it, as they're too busy bouncing it off the stand.

lol

 

Keep in mind all this keyboard slamming is done in church. I get a lot of strange looks. "He must have anger issues!"

[Tom Williams]

Wow. Just wow.

 

I spent over a year dropping my PC361 2-3" to get it to boot. I'm gonna get me some Deoxit.

[Bif_]

 

I wasn't going to assume that they'd done a firmware update on it, as they're too busy bouncing it off the stand.

 

I did some quick checking. I also have a PC3 at home and both mine and the churches are up to OS 2.20 so it looks like the 'fix' in 2.10 isn't preventing the problem.

 

I also did the "456" diagnostic procedure on my unit at home. Three of the faders send spurious data when zero'd out (at the bottom of their travel).

 

Deoxit is on the way. I'll get serious on cleaning after I get that.

[J Graul]

What was cleaned? (Keybed, pitch/mod wheel, buttons on front panel?) That would make sense as I know you're not supposed to touch anything during bootup.

 

I had a friend open it up and clean it. Pretty much everything electronic was cleaned.

[MoodyBluesKeys]

OS version 2.21 is current for the PC3 models (not K, A, or LE)

[Bif_]

UPDATE

 

Since I posted about this in November I did purchase Deoxit but never got the PC3 home to work on it. Holidays were busy and it kept working because we never powered it down.

 

In late January the church decided to replace the PC3 and based upon my recommendation we picked up a Kurzweil Forte (through Dave Weiser of course!).

 

It took a couple weeks to get it set up and in place but I didn't want to risk a failed repair attempt on the PC3 until I had a backup in place (the new Forte).

 

Last night, with Deoxit in hand, I decided to dig into this and opted to go for the easy repair attempt (reseating/cleaning the connectors visible under the user panel). The PC3 would not boot up so I figured I'd know quickly if I was successful. Within the hour all was working well. I also cleaned the sliders as a couple were wonky sometimes.

 

I spent 30 minutes playing, powering up and down and moving the board around to make sure I didn't just get lucky. All appears good. It also seems I fixed the aftertouch as it behaved weird sometimes. (Maybe that's a coincidence or I'm fooling myself.)

 

My plan now is to put that board back into my keys rig at church. I'll now have a Motif XS, Forte and PC3. I'm jazzed.

 

As always, I appreciate all the comments in this thread that pointed me in the right direction.

 

 

[MorayM]

Congrats! That's an awesome rig you've got there now.

[Bif_]

UPDATE

 

Last night, with Deoxit in hand, I decided to dig into this and opted to go for the easy repair attempt (reseating/cleaning the connectors visible under the user panel). The PC3 would not boot up so I figured I'd know quickly if I was successful. Within the hour all was working well. I also cleaned the sliders as a couple were wonky sometimes.

 

I spent 30 minutes playing, powering up and down and moving the board around to make sure I didn't just get lucky. All appears good. It also seems I fixed the aftertouch as it behaved weird sometimes. (Maybe that's a coincidence or I'm fooling myself.)

 

My plan now is to put that board back into my keys rig at church. I'll now have a Motif XS, Forte and PC3. I'm jazzed.

UPDATE

 

 

Well, it's been nearly a year since my repairs and I thought I'd post back that the PC3 is still behaving and works like a champ.

 

I'm offering this as encouragement to anyone that has a wonky PC3 as cleaning the connectors may resolve your problems.