> > > I am just about done aplayfieldswap on a bally centaur.
>
> > > On immediate powerup the1ampfuseunder theplayfieldclose to the
> > > flippers blows and all solenoids except the knocker do not work.
>
> > > However, if I clip the wires to the outhole kicker, replace thefuse
> > > and power up all solenoids fire except of course the outhole kicker
> > > and ball lauch coils.
>
> > > All coils move freely and no coils are locked on at start up.
>
> > > What I have done so far: replaced solenoid driver board with a known
> > > good working one, replacedcoilwith a used one I had that I thought
> > > was working fine and I have looked for shorts on the +43 volt bus line
> > > but have not found any.
>
> > > Short of tearing my wiring harness appart to really dig deep for a
> > > short somewhere what else should I be looking at?
>
> > > Also, all connectors have been repinned on MPU & SDB.
>
> > > Any ideas?
>
> > Sorry, I replaced the outholecoilwith a used one I had.
>
> > Could it be the outholecoildiodeor adiodeon one of the coils of
> > the ball launch mech?- Hide quoted text -
>
> > - Show quoted text -
>
> I think the replacementcoilhas a shorted outdiode, or you hooked it
> up backwards. Then the first time thatcoilfired, it took the driver
> transistor out, which is now shorted. So when you turn the machine
> on, the shorted transistor turns thecoilon permanently, which then
> blows theplayfieldfuse.
>
> Double check yourcoilwiring - the fat wire(s) must be connected to
> thecoillug that is also connected to the banded end of thediode.
> The single skinny wire goes to the other lug. If it's wired properly,
> try replacing thediode. Then replace the driver transistor
> regardless. I don't have a Centaur manual handy, but the Centaur II
> manual says that would be Q4 on the solenoid/driver board. I would
> think it would be the same on Centaur too.
>
> steve
> ---
> Steve Kulpa (cargpb10)
> Nolensville, TNhttp://
stevekulpa.net/pinball/pinball.htm- Pinballhttp://
stevekulpa.net/pinrepair/pinrepair.htm- Repairhttp://
stevekulpa.net/faces/rgpidx.htm - Faces- Hide quoted text -
>
> - Show quoted text -
Steve, thank you for your thoughts on this.
The fuse blows on start up and the coil is never energised (locked
on).
I suspect the diode is bad on that coil.
I will replace it and report back when I get home from work tonight.