Keep blowing F 115

[Ian]

I wondered if anyone can help with a problem I have on my scared stiff ,I have just replaced the flipper coils and fitted rebuild kits and now it blows f 115 the right flipper fuse when I turn it on it was all ok befor I changed the coils so I have put the old coil back on incase that was the problem but it still blows, any ideas? Tanks Ian

 

[Johnnyo]

Do you have a message on the DMD "check fuse 115 row or ground short"?

 

[Johnnyo]

Sorry just reread your post. F115 is a 50v flipper as you rightly say check your wiring as you must have a short somewhere check your wire colors to the offending flipper and I can match it to my scared stiff for you. John

 

[Ian]

Thanks John. I will have a look later and get back to you.

 

[Poibug]

If you have replaced for new coils ensure there are diodes on the coil,if not you may have took summat out.also ensure you have wired it correctly,if you wired it wrong when coil replaced,but then reconnected the originals that same way that could be it

 

[Poibug]

http://www.ipdb.org/showpic.pl?id=3915&picno=49000&zoom=1

 

[pinballmania]

115 is a primary fuse. So suspect the bridge rectifier as short. If it was a flipper coil problem the 3a fuse on fliptronics would blow first. Disconnect power to fliptronics board and retry to confirm problem is local to the power board.

 

[Ian]

I have disconnected the power to the fliptronics and the fuse is still blowing

 

[Moonraker]

So looks like a failed BR as Andy said. Next step:

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

 

[aaronhicksuk]

Isn't Scared Stiff a WPC-95 title where the fliptronics circuitry was moved on to the power driver board? If so how did you manage to disconnect the fliptronics board? Are you sure you connected the new coil in properly when you first fitted it? If you didn't you may well have blown a drive transistor on the power driver board.

If you haven't already, I would double check all your wiring is correct. Also try disconnecting plugs J119/J120 (which according to the manual supply power to the coil lugs/provide a path to ground respectively) and check the coil resistances and playfield wiring for shorts. If you turn the game on with those plugs disconnected and it still pops the fuse then theres something wrong on the power driver board, almost certainly a shorted transistor (Lower Right Flipper ones are Q90 for Power/Q92 for hold.) These are fairly easy to find with a multimeter (a good guide here: http://www.pinwiki.com/wiki/index.php?title=Williams_WPC#Transistor_.22Quick_Check.22)

Although its possible, it would be a bit of a coincedence if you were working on the flipper coils and then the flipper coil fuse popped for another reason lol! If there is a problem on the board and you aren't confident with this kind of stuff you may well be better off sending it away for repair mind.