Kurzweil 1000 Expanders
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A support site for Kurzweil 1000 series music keyboards and expanders
K1000 keyboard


Problems and Fixes for the Kurzweil 1000 K1000 and 1200*

Troubleshooting your Kurzweil*


Hard Reset: This is usually a first step when you have problems. Caution, a hard reset erases all of the user created patches and other setup changes in the RAM.  Use one of the software programs like Kurlewin or a sysex dump to save you work before you do a hard reset. On older Expanders, press and hold YES and NO buttons as you turn on the power. On the 1200 Series and some keyboards, hold A and B and turn on the power.  Select some program other than 001 before you do the reset. You will know a reset was done if program 001 is selected after the power on. If your unit is still not working then try the diagnostics (Test Mode)

Test Mode: This runs various diagnostics. On older Expanders, press and hold Program/Parameter Up and Program/Parameter Down buttons together and turn on the power. On the 1200 series and some keyboards, press C and Play/Edit and turn on the power. It takes a minute so be patient. A menu appears that you can navigate and test the RAM, ROM, OS, LCD, Buttons, and Battery. Read the service manual for details. For instance the battery test requires a special sequence. It can go over the various tests repeatedly and some tests are not fast. The ROM test takes 4 minutes. Midi Loop test typically fails and should be ignored.

MIDI SCOPE If you press PLAY/EDIT and CHANNEL UP and CHANNEL DOWN simultaneously while the unit is running the normal menu you get MIDI SCOPE, good for diagnosing MIDI coming in or going out.

Troubleshooting a failure: If your K1000 will not get to the diagnostic state read this FIRST , then follow the steps. That may fix your problem. You can also refer to the service manual- at least take a look at what it has.

A little background - how the K1000 gets to the diagnostics:
* You must push and hold two buttons and turn on the power. Hold "Program / Parameter Down," and "Program/Parameter Up" on the 1000 PX, HX, SX, and GX. On the K1000 Keyboards, hold "C" and "Play/Edit". Then the following sequence should happen.
* Power comes up and is applied to the various boards and components - 68000 CPU (and the display logic and all other circuits)
* A reset signal is generated on the PS board (after the 5 volt power comes up) and resets the display chip set, the 68000 and other circuits.
* The 68000 starts the boot up process by executing code in eproms U21 and U32 - the software engine.
* The code checks for the existence of the the Setup roms (U22 and U33 in the modules)
* The boot up checks if the appropriate two switches are closed. If they are, then the diagnostics code begins to run. If not, the unit continues to the normal operation and displays the menu.
* If the diagnostic switches are closed, the diagnostic code then sends the diagnostics message "KURZWEIL 1000 TEST SUPERVISOR" or a similar message to the display, and after a second or so, displays the first menu option and waits for the operator to select tests.
Note: If you want to see the details, read the service manual.

Possible reasons diagnostics will not run: Your K1000 needs to get to the diagnostics before you trouble shoot anything else (Relay clicks, bad OS, Bad Sound chips, etc.)If the above "core" process to get to the diagnostic mode does not work, then one or more of these following things could be bad. (This is a partial list of course, but based on the experience of the group.):
- There is a loose connection or a corroded connection somewhere - the most likely cause!
- The power supply has failed: There could be a bad PS board solder joint (most probable), corroded trace, or bad component (probably a capacitor).
- Power is not getting to the CPU Board/components: There could be a loose or bad connector on the cables or a broken/corroded circuit board trace..
- The reset signal from the power supply is not getting generated - or not connected to the CPU board: Again, bad connectors/ traces / solder joints or components.
- No clock is being applied to the CPU and or other circuits: The clock generation components have failed (not likely).
- The 68000 CPU died. This is very unlikely.
- The engine eprom(s) has failed or is not making good contact in it's socket. This is where the diagnostics code resides - eproms U21 and U32. In the modules only, U22 and U31`(the setup eproms) are also checked and if either of them are defective or not making good contact - the diagnostics will fail.
- Another component necessary for the core diagnostic process has failed. Here is a partial list of possible failures:
   - Connector/cable between the CPU board and display.
   - Connector/cable between switches and CPU board.
   - Switches used to start the diagnostics are not closing, dirty or broken.
   - The LCD Display has failed.
   - LCD Display driver chips failed.
   - Chips to route switch pushes to CPU failed.
   - Clock circuits failed.
   - The backup battery has shorted or corroded the board.
        Note: A dead or removed battery will NOT cause a failure - the unit will just not save any user changes that are saved in RAM.

Diagnostics won't run - What to do: If you cannot get to the diagnostics, go thru ALL of the steps and checks below. The order of the checks is based on previous failures and some logic. Do everything before you ask for help on the K1000 user group. This sequence assumes the unit stopped working after it WAS working. I.E. you have not changed chips, have not moved jumpers, that no chips or transistors have failed (they seldom do), that you did not drop it 20 feet and break a circuit board and that you have checked the fuse and plugged the unit in - ha ha! You will need a soldering tool and a VOM that measures DC and AC. You can do most of this without an oscilloscope and may have a pretty good chance of fixing the problem. This assumes you know a little about electronics and the dangers or high voltages - they can kill you!  If you need help, find a friend that has some experience.

First, does the display have life?
- After you try to initiate the diagnostics, check the LCD display. Does it show anything at all. It will show boxes if receiving the proper power but no data. If you see nothing then there is a good chance no power is reaching the display so the power supply is suspect. If you see boxes, then power is arriving at the display but no data. Cables, eprom sockets, connectors, bad capacitors etc. are now probable failure points. If you see garbage or jumbled letters then you have probably already been mucking around and need to go back to the original configuration and start over.

CAUTION: These units have dangerous voltages that can kill you! NEVER NEVER work on the unit with the AC cord attached unless you are measuring voltages. If you are not experienced with electronics - get some help. YOU and only YOU are responsible for safety.

Next, see if the proper power is going to the various places:
- Open the unit and use a DC voltmeter (VOM) to check every power supply voltage. Refer to the schematics for pin numbers on the various connectors for locations of where to check voltages. Repair the PS (above list) until you get all voltages as they should be.
- If there are no dc voltages, perhaps P1 (the connector to the transformer) is bad.
- Check voltages on the 68000 CPU (Pin 14 should be +5 volts relative to ground). No voltage or a wrong voltage could indicate bad connections (likely) or a bad circuit board traces (likely if you see corrosion)
Be very careful measuring voltages on IC pins so you do NOT short two pins together. That will destroy the unit.
- Check the voltage between pin 28 and pin 14 (ground) on the eprom chips with version labels - K1000 U21 and U32 and also U22 and U33 in the modules. These chips are required for the diagnostic code.
- (Optional) Set the VOM to AC and see if any AC (ripple) exists on the DC voltage points. (A poor man's check without an oscilloscope) 0.05 Volts AC or less is normal. If you see more than 1 volt AC you probably have a problem with power. If you measure 5-10 volts AC, the unit may run but you will hear hum on the audio. 20 volts or more then all the caps are bad. Double check the capacitors or get an oscilloscope to troubleshoot the power supply if appropriate.
- While you are here, check the voltage on the backup battery on the mother board with the AC power cord removed. If it is bad replace it now. (link to details)

Still not working: Next, after all the voltages look good, see if there is a bad connection or corrosion - the most common problems (These steps are with the power cord removed):
- Pull and clean the connectors between the power supply and CPU board. Just pulling and replacing them may help.
- Clean up other visibly bad connectors - pull and replace a few times and/or use a cleaner.
- The connector between the CPU board and the display.
- The connector between the CPU board and the front panel switches
- Carefully pull, then replace the OS eprom chips with version labels - U21 and 32 (and U22 and U32 in the modules*). This is most important if you see signs of corrosion. One or more pins may not be making good contact. Be careful with the chips.  To remove them carefully pry up each end just a little at a time.  Use a chip pulling tool or make one - it should have a short  1/8 inch 90 degree bend and a flat surface like a screw driver so you can get under the edge without damaging surrounding components. Here are some tipsHere are more tips.
- Remove the power supply board and inspect both sides.
NOTE: Due to the numerous failures experienced with the power supply, once you pull the power supply board, AWAYS replace any obviously bad capacitors and ALWAYS re-solder all the joints on P1 (the connector going to the transformer) and the power connector to the CPU board. If you don't, they are going to fail sometime in the future.
- Visually inspect the Power Supply board for other corrosion, bad solder joints and or bad capacitors. Swollen or corrosion around a capacitor is a sign the capacitor may be bad and that a trace or solder joint is bad. Re-solder any other joints that look suspicious - especially those where capacitors are soldered onto the board. Check suspect traces with your VOM (ohms). If a tract is open/broken, clean off the varnish and bridge the break with solder. Another thing to check
- Pull the CPU board and look at the big cap (1000uf) below the eproms on the K1000 CPU board. (location is different on the modules). Look on both sides of the board. If it has leaked or the leads/solder joints are not shining like the others are, then there is a good chance for corroded traces on the CPU board. This is VERY common - like almost every K1000 that one of our members has repaired in the last 10 years - lots! You can check the traces around any found corrosion with your VOM ( ohms) with the unit UN-PLUGGED!
- Find all the other chips in sockets or jumpers could have corroded pins and remove and clean them. The Arnold (big square chips) are difficult and require a special tool, so you may want to wait till last to pull them.
- Check the Play/Edit and C switches (K1000) or Program/Parameter Down," and "Program/Parameter Up on the modules. Make sure they are working - I.E. shorted when you push them.

Still not running diagnostics: If the unit still does not boot to the diagnostics, next, see if the CPU clock is running:
- Put a DC voltmeter between pin 15 of the 68000 CPU (the clock) and ground. It should read somewhere between 0 and 5 volts if the clock is running. This step really requires an oscilloscope. If the voltage is very near 0 volts or 5 volts you will need to find one to continue.
- If, at this point you have fixed all obvious problems and your unit will still not boot or go to diagnostic mode you will probably need and oscilloscope and / or refer to a qualified repair person. However, if you have and oscilloscope:
    - Check pin 15 of the 68000 for the clock. It should running and be 10 megahertz.


OK, so you got the diagnostics to run and they all check out OK but the unit still does not have sound:

- If it looks like the unit is working, the display is good, there is sound using headphones in the headphone jack but no sound out the audio output jacks then check the relay. Refer to the rest of this page for other special situations and to the schematics for possible places to look. Double check the Sound ROMS pins and sockets, the Arnold chips, all front panel buttons ETC. Again, don't spend a lot of money or time unless you are having a lot of fun. A dead unit is not worth much. A dead keyboard is not worth what it costs to ship it anywhere. However, some members of the group do look for used keys and other parts so you might consider parting it out.


Additional and Supplemental Information

Hard Reset

Caution, a hard reset erases all of the user created patches and other setup changes in the RAM.  Use one of the software programs or a sysex dump to save you work before you do a hard reset. On older Expanders, press and hold YES and NO buttons as you turn on the power. On the 1200 Series and some keyboards, hold A and B and turn on the power.  Select some program other than 001 before you do the reset. You will know a reset was done if program 001 is selected after the power on.

Test Mode

This runs various diagnostics. On older Expanders, press and hold Program and Parameter buttons together and turn on the power. On the 1200 series and some keyboards, press C and Play/Edit and turn on the power. It takes a minute so be patient. A menu appears that you can navigate and test the RAM, ROM, OS, LCD, Buttons, and Battery. Read the service manual for details. For instance the battery test requires a special sequence. It can go over the various tests repeatedly and some tests are not fast. The ROM test takes 4 minutes. Midi Loop test typically fails and should be ignored.

ROM 33 I saw the following error message: er 4 lset rom -33 reported by Daniel in Argentina

This message was related to improper motherboard preparation. Checksum is the total number of 1's and 0's on the chip in question. This number is known and embedded in the OS. The OS has come up with a wrong number during self check. This could be 1) defective chip OR 2) the OS is not able to check the chip (motherboard) Checksums are printed on original OS chips, you can see them on the sticker. 

Power Problems

General: Many users report that the P1 connector on the power supply board is the root of many startup and other problems. (Especially the HX modules) (See also below)

Common and running problems. Everyone reports that the P1 on the bottom side of the power supply board gets "cold" and fails to make a good connection. This is known as a 'cold solder'. The solder is gray and dull rather than shiny and bright. With a soldering gun reheat and bond the solder. Don't touch or move the board while cooling (the cause of the cold solder). This may have been a production problem. Of the 11 modules I have, 3 have had P1 problems. This problem is sometimes so elusive that it appears to be any other problem. If something doesn't get better quickly I would re solder the P1 connector just because you have it open. You may be pleasantly surprised! 

User report

Just wanted to update you on my progress. I tried all the suggestions the group gave me, reseated the chips, checked
the power supply. I found a cold solder joint on the 22000uf 16vdc electrolytic capacitor on the power supply board,
the big one. Boots up fine, and now I can use it. It's been a good week. Thanks for all your help, Robert. 
P1 connector

No sound or Distorted sound

This is most often caused by a faulty audio output relay - a relay that connects the audio to the two output jacks on the back of the expander or keyboard. If the relay gets stuck or fails, no sound will be heard at the output jacks. Sound will be heard thru the headphone jacks on the keyboards even if the relay fails.  Solution is to tap on the relay, take it apart and clean it to get it working then, purchase a new one. If the relay is amber Omron or Mitsu (non sealed with a pop top), it may very well be bad. If it is a yellow Panasonic or black Zetler (sealed units) it is less unlikely to be bad.  

Two symptions:
No sound: The bootup sequence should have an audible click about 3 seconds after the ON button is pressed. If no click the Relay on the mother board is could be stuck. Open the unit and tap gently on the relay. On the Motherboard is printed # Q 005 a box labeled "zettler", over near the audio outs. The relay connects the audio to the output jacks. Tap on it gently. It's a plunger that moves and it gets stuck in the mud. If it doesn't click after tapping, tap harder.  A relay is a standard electronic part.

Distorted sound: One user (Mike) experienced distorted sound. He actually replaced the output amplifiers (with no change) then finally checked the relay. In this case dirty contacts were causing the problem. He cleaned the contacts with contact cleaner and some 'emery' paper and the problem went away. He will replace the relay next time.

Relay part no. Here's the relay that I used for repair of my K1000: Aromat/Panasonic DS2Y-S-DC12V Digi-Key item # 255-1079-ND. Cost: approx. $2.65 (+S&H) -Dallas (thanks Dallas!)

Won't start or No Sound

Plugged in? fuse on the power supply board? Most do not have a fuse. A few early modules did. Power to P1 connector? 

After an upgrade: ROM chip is HOT? You inserted it backwards.  Check audio board area for burn marks, audio boards seldom fail. If you insert a chip backwards you can kill your entire module. BE CAREFULL. 

Cyclic clicking? The P1 connector needs to be resoldered. Remove the power supply board and solder it from the bottom side. Power supply manufacturing issue: board with the copper traces for the 5VDC secondary go bad. The surface area of the copper traces is too small to handle the current for 5VDC, they go bad and the 5VDC goes out of regulation. One user reports all 4 of his did this. 

Keyboard Story

For an interesting tale of the wiring under the Keyboard. This is a rare problem. see dead-keys for more information.

LCD light

They grow dimmer with age and finally go out. The original is a Seiko M1632, widely available for less than $10. Seiko Model M1632, tech sheets and data can be found at the web site. http://www.eio.com/m1632ap.htm OR Densitron LM4262 depth 14 cm Densitron LM2162 depth 10 cm http://www.densitron.com/displays/products/?o=1&cat=1&id=1 Installation instructions can be found here backlight-fix.  This is a difficult change because of space requirements. Telesisgear.com http://backlights.telesisgear.com <http://backlights.telesisgear.com/> .
They are friendly, reasonably priced, and excellent instructions. 

Weird behavior

Sometime pins in sockets get oxidized. Pull each chip carefully and clean carefully. Use standard chip puller. Digital noise that appears random, AFTER an upgrade? David G has discovered that some of the boards had JP05 hanging in the air and wasn't connected to anything. Instructions/info on upgrades page and chip data page.

Here is a typical fix it story related to oxidized pins/sockets - from June 2008
(Names removed by webmaster)
User:  My K-1000 is 15 yrs old and after a cross ocean voyage and an 8-year stint in bone dry but roasting temps in a garage in a flight case, it makes weird sounds when more than 1 key is played. Some sort of off pitch reverberation randomly triggers. Neither the "reset" nor the "test" functions work, according to the procedure mentioned here. Nothing happens. Although I just bought a chip puller and have an array of small flat screw drivers, I'm really scared to start pulling chips off to clean oxidation that is not readily apparent to me. I'm scared the tiny legs will either break off or not insert back in. Also, I don't want to pull off something that's not meant to come off. Any advice from someone who's done the oxidation removal or has a different repair in mind to suggest? I'm grateful for any insight to help me avoid ruining something I love.
Helper1: Pull off the OS chips and clean the legs. The OS chips will permit you to self test. Don't be afraid, pull the ones in sockets. We can replace any chip that's in a socket but for now remove only the U21-22-31-32 and clean them. It's got to be one of those chips or the P1 connector which is all on the website.
User: Found the U21 and U32 chips immediately and though there was no visible oxidation I pulled and cleaned them with alcohol.  Spent a couple of hours going through the schematics to find the U22, U31 chips without success. In any case, before getting set up for the P1 routine I decided to power up and behold, just like new. No noisy artifacts. All fixed!  Thanks!
Helper1: That's GREAT! You might think about running the self test and it will tell you if any other chips are needing a little work. The procedure is in the manual, a bunch of button pushes an wait while it tests everything.
Helper2: You couldn't find the other 2 chips? The 4 OS chips are in a square next to each other. Don't look at the schematics. Look at the board. I have my doubts about the alcohol cleaning. You cannot remove oxidation with alcohol. The pulling and putting them back probably did the trick.
Note from webmaster: The K1000 Keyboard has only two OS/Setup Chips. U22 and U31 do not exist in the Keyboards.
Follow up: Here is how to clean contacts on the chips. Carefully clean the pin legs on the chips. Best practice is to wipe them gently with an eraser. If your comfortable with a little vinegar (acid bath) OK but just paint it on the legs with an artists brush then paint the legs with water and dry. Other things that work are brillo abrasives (NOT the steel wool pads) but the kind that come on the back side of a sponge in a green layer. With a BRAND NEW brillo abrasive gently wipe the pins without bending in the direction away from the tips. It should take about 20 wipes on each side and gently. We can replace the chip but it's gonna cost ya about $8-12 depending on chip prices.

Sounds seem like random waves?

Electrical connection on a chip is lost. During insertion of a chip you bent, broke or failed to insert a pin. A ROM chip is in the wrong socket. Oxidation

Boot up freezes

Display shows: DATA PC 42010080 / 80037C 42010080 This is what was displayed when 2 RAM chips were added. On power up the screen froze and displayed this, and the instrument would not respond to any commands. This was an experiment by Andrea Toni in the Netherlands to increase the amount of memory. The Kurzweil was smarter than Andrea. 

Screen freezes: generally this means the OS can't complete it's boot sequence and any work that you just did needs to be carefully reviewed.

More from another user:  "db, are you aware of an issue with the power supply board with the copper traces for the 5VDC secondary going bad?  The surface area of the copper traces is too small to handle the current for 5VDC, they go bad and the 5VDC goes out of regulation.  I own four 1000 series boxes, had to fix that problem for all of them."  -analogdiehard 

Will not save programs/patches setups

This could be a dead backup battery. The batteries are designed to last 5 to 10 years. Some last less, some longer. You can replace the battery but be very very careful. They are soldered into the circuit boards. You can not apply heat for more than a few seconds and if you apply too much heat the battery may explode or be ruined at the least. Do not attempt this if you are not experienced soldering to batteries. Best to get an experienced technician to do the spot weld type soldering to to it right!


Known repair guys

Advanced Musical Electronics in LA, USA
Synth Service Centre, London England
if you know any more repair centers email me from the contact page.

Parts are here: 

http://www.dgaudiorepair.com/vintage.htm They have a list of all sorts of stuff that changes.

The P1 Connector can cause almost any problem.  Below is the way it looks when it's bad.  You may need a magnifying glass to see the fracture locations.  This one required considerable magnification to see it.  

This is on the bottom of the power supply board which must be removed.  It's probably smart to resolder this connection if it hasn't been done since manufacture date.  

Below is what it looks like when it's resoldered.  This is a common problem.

Thanks to user group member for the great pictures!  

* From the ex-Alzerom site with approval of David B.  (Some mods made by web master)