Pinball Nirvana Home Page

Go Back   Pinball Nirvana Forums > Real Pinball > Maintenance & Repair

Maintenance & Repair Discuss and offer tips on real life machines.

Thread Tools Search this Thread
Old 01-02-2019, 11:56 PM
gchase59 gchase59 is offline
Inserted Coin

Join Date: Jan 2019
Posts: 6
Credits: 148.12
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
gchase59 is on a distinguished road
Default Stern "Pinball" pinball game MPU keeps resetting

Stern pinball game just stopped working. I check the 43VDC test point TP5 and found no voltage. Fuse was blown and when I replace it it blew immediately. Rectifier board was pretty beat so I purchase a new one. Plugged it in a blew the fuse for 43VDC. Found the coil for the clacker was shorted so I unplugged it and the game started right up. Started play the game and after a couple games it reset in the middle of a game. I opened the back and could see the MPU board go through selftest and start back up. This continued to happen intermittently. I started monitoring voltages with a DMM and noticed I got an AC reading on the 43 VDC. I got an oscilloscope and looked and I see a lot of ripple on some of the DC voltages. Looks like what you would see after a bridge rectifier but before it had been regulated. Is that normal? Wondering if it is filtered and regulated by the solenoid board?

Thanks for the help
Reply With Quote


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump

All times are GMT -4. The time now is 11:53 PM.

Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Template-Modifications by TMS
Credits System provided by vBCredits II Deluxe (Lite) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Shoutbox provided by vBShout v6.2.15 (Lite) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.