This has been driving me nuts

I have replace the BR2 recitifer on my STTNG. It has been replaced at least 3 times which causes the game to reset while playing. The third time was with this one from pinball life which is rated at 600V instead of the typical 200V one

http://www.pinballlife.com/index.php?p=product&id=411

I followed many of the troubleshooting tips on pinwiki here

http://www.pinwiki.com/wiki/index.php?title=Williams_WPC#Game_resets

1. Line voltage tests fine
2. Ground is good
3. See no visible cracks in Driver board on 5V area
4. Checked all Diodes on flippers. Look fine
5. BR2 fails based on PINWIKI troubleshooting

After each replacement of the rectifier the game is fine for anywhere between 3-5 hours of play. After that the system begins resetting, you check the BR2 and its shot again

Only thing I have not checked is thermistor. That will be done after work today. IF this is fine I am at a loss and any advice would be appreciated

Thanks

Running the test as shown on PInwiki.
1.Place your DMM into "diode test".
2.Put the black lead of your DMM on the "oddball" lead of the bridge rectifier. This will be the lead that isn't oriented the same as the others (as with the "spade" type of bridge) or the lead that prevents the four legs from forming a square (as with the "wire lead" type of bridge). This will also be the DC positive lead of the bridge.
3.Place the red lead of the DMM on each of the adjacent legs, one at a time.
4.A reading nominally between .5 and .7 should be seen (this represents the voltage drop across the bridge's internal diodes).
5.Now place the red lead of the DMM on the lead opposite of the "oddball" lead, or the DC negative lead of the bridge
6.Place the black lead of the DMM on each of the adjacent legs, one at a time.
7.Again, a nominal reading between .5 and .7 should be seen

I get .3 to .4

M

My freidn did the work. He just replaced the bridge. He's done it 100 times on other boards

Fuses were checked. All ok. My friend who replaced board checked all solder places on Driver board. He said all seemed ok.

Wish I could if I had a spare

Did not test outside of board. Only test I ran is as in thread post 2 posts up. Followed the PINWIKI test. accroding to that test it is bad.

It ran fine for about 4 hours after the last replacement then the same reset symptoms came right back and you can't run it for more than 5 min now and reboots.

Small Update folks

Think I may have found the cuase of my rectifiers blowing.

Opened up the ON/OFF Switch box to look at the thermistor. Went to turn it over to check the number and it crumbled in my fingers. Bareley even touched it.

Hopefully replacing this fixes the problems

A. Thanks for the advice but no need to be snotty about it. And by 100 times if you took that literally it was just meant as a he's done work of that sort plenty of times so he knows how to put them in. If you wern't being snotty I apologize but thats how it came across

B. Every time we replaced the bridge it works fine. Then all of a sudden it start resetting. Replace bridge again works fine for about the same time frame

As in my post above I found the thermistor was aparently bad. Will be replacing it and see what happens

Thanks for the advice

Thanks. Will definitly check this. If it is failed may contact you on how to repair if you don't mind

Thanks again

I apoligize for accusing the post of being snotty. Sorry Borygard (Truely) Thats just how I took it. My bad. Thank you for pointing out I need to be more specific.

I have the thermisitor on order. Hopefully will arrive soon. Will let you know after replacement

Here is the final update. Have replaced the thermistor. I also measured BR2 and it was showing a low voltage according to the Piwiki Troubleshooting. So I replaced that.

All seems to be well now. System was played for over 6 hours straight with no issues.

Thank you all for all your help

I will be posting a picture in a new thread of my finished machine

Again thank you all for the help