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PSR Keyboards (11 Boards) => PSR-S970/S770/S670 (SFF2) => Topic started by: imzain786 on July 25, 2021, 04:35:48 PM

Title: S970 sd ram issue
Post by: imzain786 on July 25, 2021, 04:35:48 PM
Hello ,
Last night suddenly i am facing this unexpected error. In testing mode.
What can i do? How to hard reset or troubleshooting this error.

main Sd ram IC(205, 206, 201, 208 ) NG

I can't upload screenshot due to file size restrictions
Title: Re: S970 sd ram issue
Post by: overover on July 25, 2021, 05:52:55 PM
Hi imzain786,

if you don't have the S970 Service Manual, please download it here:
>>> https://psrtutorial.com/lessons/workshops/ServiceManuals.html

The only thing you can do yourself would be to start the internal Test Program and execute the following test routines (including a complete Factory Reset):

- Start the Test Program (using one of the two methods described on page 39 in the Service Manual.

- Execute test "002 : Memory Check1 All". (It's best to take a photo of each error message.)

- If the result is OK, execute "083 Test Exit" and check whether the S970 restarts normally now or not.
- If the result of test No. 002 is NG, execute the tests 003 - 009 (simplified ROM/RAM checks). Probably "005 : RAM Check1" will fail (NG).

- Execute the tests 067 - 073 (complete ROM/RAM checks). Probably "069 : RAM Check2" will fail (NG).

- Execute "081: Factory Set".

- Execute "083 : Test Exit". The S970 should restart now and "Force Format Mode" should be shown for a while.

If you're lucky, the S970 now works normally again. But if you get the error message "Main SD RAM ... NG" again, only Yamaha support will be able to help you. The mainboard would probably have to be replaced.

The ICs mentioned are all on the S970's mainboard (DMH circuit board). However, this spare part is not cheap: at the German company "www.audio-service.com" the DMH board of the S970 (Part No. ZN123700) costs around 415 euros ...


Hope this helps!

Best regards,
Chris
Title: Re: S970 sd ram issue
Post by: johan on July 25, 2021, 06:51:52 PM
Indeed most probably a hardware problem. You could try to unplug your keyboard for a day or so to make sure all static electricity has gone from the RAM chips but few chances that this solves the problem.
Title: Re: S970 sd ram issue
Post by: imzain786 on August 11, 2021, 09:55:22 AM
Can i replace my s970 DMH board into s975 DMH board.
i mean to said, i have s970, can it fit or work fine S975 DHM board in my S970 body ???

regards
ZAIN