WTB Sega Super GT Servo (ffb) [working]

[Neozone]

Hey I am looking to purchase a Sega Super GT force feedback board. I see some have been for sale in the past in the forums but didn't see much recently.
My main game PCB on one cab is not working so I will need to work on that to see if I can get that working also but for know i have swapped servo boards and one is not working. THANKS!!

 

[Neozone]

Sega Super GT

Hey I am looking to purchase a Sega Super GT force feedback board. I see some have been for sale in the past in the forums but didn't see much recently.
My main game PCB on one cab is not working so I will need to work on that to see if I can get that working also but for know i have swapped servo boards and one is not working. THANKS!!

or if anyone knows if its possible to repair the board that would also be helpful. there is so much intregrated stuff on the PCB that I am really not sure how to test or where to begin. but i have a working cab so i know the board is bad

 

[Mylstar]

do you have the Sega part #?

 

[Neozone]

Looking at my manual it looks like the part # for the servo board is:
838-12912 [Servo motor drive BD SPG]

 

[Neozone]

though I will add that when i search that part # online it does not look like the board i have. very similar but not identical.

 

[Hydreigon]

I noticed there are two drive boards, a main and motor board. It looks the main board would send commands to the main drive board and again to the motor board to control the motor. I would also swap the main drive boards (the one with a rom) to see if the issue follows the other side. Possible problems could either be the caps or transistors.

I was almost used to Daytona 1 only having one drive board as opposed to two.

P.S. I would take a good pic of that rectangular chip in the center to see what type of component this is. This board doesn't look like it was manufactured by Sega at all. Most likely from Matsushita/Panasonic.

 

[Neozone]

Swapped.

Thank you for the response. The board with the eprom is the drive board. The other is the servo board. I have swapped and issues only follow the servo board i have pictured above.

 

[Neozone]

Square chip

Pic of square chip near center of board. Seems to be Mitsubishi.

 

[Hydreigon]

M37704 family CPU/Microcontroller. Mitsubishi makes some good stuff so it's unlikely the MCU is the culprit. Looks to be a rare variant but it's possible a M37702 could work.

I'm leaning towards a worn out transistor (one or more). Some of these are required to amplify the correct current needed to drive the motor otherwise a motor or solenoid would do nothing (like how the blue gun on my Time Crisis 2 wouldn't recoil due to a dead transistor).