Re: Grand Lizard, no coils firing

On Apr 26, 10:34 pm, Drewscruis <Drewscr...@xxxxxxx> wrote:
On Apr 27, 1:17�am, PinBrawler <Vdubchand...@xxxxxxxxxxx> wrote:

I have agrandlizard(system11 I believe) and all thecoilsdont
work. I dont have much experience on pre-1995 pins, does anyone have
any idea of what to look for. Any places to measure, what to look for,
things I'm missing?

I did check the fuses and reflowed most of the cold solder joints, if
I had a problem with the door interlock switch would that cause the
coilsnot to work? anyways I dont know what's up and I need help

thanks
jake

check the bridge rectifier's on the aux power board ( i think it has
one, if not check the bridge's by the large cap) also make sure that
all the plugs are properly installed, maybe you possibly over looked
one. also check to see if you have voltage going to any coil, just
take a multimeter set it to dc take the black lead and attach it to a
ground strap in the cabinet and check to see if you have any voltage
to the coil should be over 30volts I can't remember exactly. if you
don't have any voltage then you may have a bad bridge, if you have
voltage then you may have a bad mpu (doubtful, I've never seen every
output transistor blown, but you never know.) and if you want to
manualy fire thecoilstake a piece of wire and hook 1 end to ground,
then touch the back of the transistors on the mpu in the lower right
hand side (two rows of 8, should be tip 122's) and that will fire the
solonoid, only do this for a short time to see if it fire's don't hold
it there for an extended time, you could short the coil out. and in
the upper right hand side of the mpu there also should be a bank of 6
( 2 rows of 3) tip 122's thoes are the speical solonoids, you can do
the same with them to see ifcoilsarefiring, also doing this some of
the transistors control flash lamps, so if you do it and a light comes
on don't worry it's supposed to. if that all checks out then I dunno.
good luck

ok well I did swap the bridge rectifier on the aux board-nothing

I also thought I would swap the two bridges on the back box above the
big cap but nothing either, I didnt notice if I had GI when I swapped
the bridges, I just remember only feature lamps. I guess the person I
got it from was rebuilding the flipper and I dont think they turned
the game off, that's why I'm suspecting sometype of electrical part
out. Also I will try to short the coil out, If I remeber I did check
the voltage and there was non there.
.

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