Firepower... on Fire! (Smoking)

Hey everyone,
It's been a while, with my move and packing and unpacking and all other life things, I've hadn't had opportunities to play or work on some of my families pinball machines, or even my own. A while back (and there's a post someplace about it on the forums) My dad and I got a Firepower machine, after some tinkering and repairs its up and running.... almost. The issue now is the one of the pop bumpers solenoid (I believe its the closet one to the player, it's been some time since I last touched this machine) is stuck on and over heats. So 2 questions, what part number is this solenoid? and more importantly, what should I check that could be causing this solenoid to get stuck on, heating up, and smoking?

Thanks everyone in advance! It's been a while and I'm more rusty than ever... drats... just trying to get back in the right mindset and back on my pinball fixin, playing, loving track!

#2 4 years ago

WOT

Atari_Daze

Spd

Houston, TX

7y 141K 10,053 7

Suspect a stuck switch.

Switch / Solenoid File obtained here:
https://www.ipdb.org/search.pl

Beginning pin repair on Sys 6 machines:
http://www.pinwiki.com/wiki/index.php?title=Williams_System_3_-_7#System_6

pasted_image (resized).png

#3 4 years ago

237

slochar

Pinside member

7y 86,550 6,913

Not the switch matrix switch though - it's going to be a special solenoid switch/circuit that's locked on - these don't show directly in the switch matrix test. You will see whichever scoring switch is stuck on as a result of the special solenoid being on, but that is a secondary symptom of the core issue.

Pinwiki site is fine just look in the special solenoid troubleshooting section - likely you have a shorted transistor or logic chip on the driver board. Logic probe is the best diagnostic tool to find it you can go from input to output fairly easily. It's going to be the furthest component bad that has good input but bad output. Start there.

#4 4 years ago

JON

Schwaggs

It could be a stuck switch or a blown driver transistor or other issue on the board.

To test, remove 2J13 which is the special switch input on the upper left side of the driver board. If the special switch on the pop switch stack is the culprit, the pop will not lock on with this connector removed.

If it still locks on, you have an issue on the driver board.

9 months later

#5 4 years ago

JKA

JohnnyPhantom

Pinside member

It's been a while, but I got back to the machine, unplugging 2J13 did nothing, but unplugging 2j12 stopped the power going to the pop bumpers, what does this tell me as far as solving the issue?

Thanks everyone!
~John

#6 4 years ago

AMS

barakandl

OP
Quoted from JohnnyPhantom:
It's been a while, but I got back to the machine, unplugging 2J13 did nothing, but unplugging 2j12 stopped the power going to the pop bumpers, what does this tell me as far as solving the issue?
Thanks everyone!
~John

The solenoids are locking on with their triggering switch on the playfield is disconnected. That pretty much means the driver board has a problem in the special solenoids which include 7408, 7402, 2n4401 and TIP102(equiv) in the top left area.

When the special solenoids lock on for a long period it seems to kill the 7402/7408 chips.

#7 4 years ago

JKA

JohnnyPhantom

Pinside member

Thanks for the reply, I'm not to familiar with system 6 machines or logic probes, but I don't mind soldering. should I just replace the 7402, 7408, 2n4401, and the tip102 in to top left of the driver board?

#8 4 years ago

JON

Schwaggs

OP
Quoted from JohnnyPhantom:
Thanks for the reply, I'm not to familiar with system 6 machines or logic probes, but I don't mind soldering. should I just replace the 7402, 7408, 2n4401, and the tip102 in to top left of the driver board?

Let us know which specific coil is locking on (which pop bumper) and we can tell you which transistors and chips are in the signal path of that solenoid.

I'd start by replacing the pre-driver and driver transistors for that coil.

#9 4 years ago

JKA

JohnnyPhantom

Pinside member

Quoted from Schwaggs:
Let us know which specific coil is locking on (which pop bumper) and we can tell you which transistors and chips are in the signal path of that solenoid.
I'd start by replacing the pre-driver and driver transistors for that coil.

IMG_20200418_132617 (resized).jpg

#10 4 years ago

AMS

barakandl

OP
Quoted from JohnnyPhantom:
Thanks for the reply, I'm not to familiar with system 6 machines or logic probes, but I don't mind soldering. should I just replace the 7402, 7408, 2n4401, and the tip102 in to top left of the driver board?

If you are 100% confident in your soldering skills replacing all four chips, 2n4401, and tip102 in the special solenoid area will probably fix it but I would probably investigate more. This is a pretty simple circuit and probably a good place to start to get handy with a logic probe.

Use 74F or 74S chips in the special solenoid area,(ie 74F08) and not 74LS and 74HC(T).

Untitled (resized).png

IC7 and PIA CB2 used to keep the special solenoids from working in attract mode. I don't think that is relevant to your problem. It mixes in with the blanking in the picture above to disable special solenoids.

#11 4 years ago

JKA

JohnnyPhantom

Pinside member

Quoted from barakandl:
If you are 100% confident in your soldering skills replacing all four chips, 2n4401, and tip102 in the special solenoid area will probably fix it but I would probably investigate more. This is a pretty simple circuit and probably a good place to star to get handy with a logic probe.
Use 74F or 74S chips in the special solenoid area,(ie 74F08) and not 74LS and 74HC(T).
[quoted image]
IC7 and PIA CB2 used to keep the special solenoids from working in attract mode. I don't think that is relevant to your problem. It mixes in with the blanking in the picture above to disable special solenoids.

I'll see if I can find a logic probe and give it a shot, but I'm 100% confident in soldering, I've done a ton and have a nice hakko desolder gun and solder iron

Would you be able to show me the section the chips are in? and curious, I have the schematic book infront of me, and under the bill of material i see TIP120 listed but nothing for TIP102, is it 102 or 120?

thanks again for all the help, I really appreciate all of this

#12 4 years ago

AMS

barakandl

OP
Quoted from JohnnyPhantom:
I'll see if I can find a logic probe and give it a shot, but I'm 100% confident in soldering, I've done a ton and have a nice hakko desolder gun and solder iron
Would you be able to show me the section the chips are in? and curious, I have the schematic book infront of me, and under the bill of material i see TIP120 listed but nothing for TIP102, is it 102 or 120?
thanks again for all the help, I really appreciate all of this

TIP102 is a beefier version of TIP120. The kind of flippers are a special solenoid too so i circled it too.
Untitled (resized).png

#13 4 years ago

JKA

JohnnyPhantom

Pinside member

Quoted from barakandl:
TIP102 is a beefier version of TIP120. The kind of flippers are a special solenoid too so i circled it too.
[quoted image]

Awsome thanks for all that, I'll get the TIP102's next question, the 7408's are out of stock at great plains, would any of these work as a substitute?

Screen Shot 2020-04-18 at 1.43.55 PM (resized).png

#14 4 years ago

JON

Schwaggs

OP
Quoted from JohnnyPhantom:
[quoted image]

That is the bottom right jet bumper.

Driver board J12 pin 6

Q8 - Driver Transistor - TIP 120 (stock) but replace with TIP 102 (stronger) but OK to use TIP 102 if you have one
Q7 - Pre-Driver Trans - 2N4401
IC8 - 7402
IC6 - 7408

All in the upper left corner of the board. You can check the manual for a picture with a specific component diagram to find their location on the board.

#15 4 years ago

AMS

barakandl

OP
Quoted from JohnnyPhantom:
Awsome thanks for all that, I'll get the TIP102's next question, the 7408's are out of stock at great plains, would any of these work as a substitute?[quoted image]

Use 74F08 and 74F02 if the no letter ones are not available.

2 weeks later

#16 3 years ago

JKA

JohnnyPhantom

Pinside member

Hey everyone, wish I could say the machine is up and running. But not yet. I've replaced the parts mentioned above as well as a new solenoid. Now when I power the machine on, the 2.5A fuse on the power board blows. The one for the solenoid. I tripple checked my solder job a few times, no bad solder points, no sorts. I'm pretty sure I put the chips in correctly. I put sockets in the board to make it easy in the future next time. As far as I can tell the chip orientation is correct, but can someone confirm? What else could I check?

Thanks everyone!

IMG_20200502_131255 (resized).jpg

#17 3 years ago

JKA

JohnnyPhantom

Pinside member

OP
Quoted from JohnnyPhantom:
Hey everyone, wish I could say the machine is up and running. But not yet. I've replaced the parts mentioned above as well as a new solenoid. Now when I power the machine on, the 2.5A fuse on the power board blows. The one for the solenoid. I tripple checked my solder job a few times, no bad solder points, no sorts. I'm pretty sure I put the chips in correctly. I put sockets in the board to make it easy in the future next time. As far as I can tell the chip orientation is correct, but can someone confirm? What else could I check?
Thanks everyone!
[quoted image]

Hmm looking at my before and after pics. I may have the 7402 chip reversed on the bottom. Can anyone confirm?

#18 3 years ago

JON

Schwaggs

OP
Quoted from JohnnyPhantom:
Hmm looking at my before and after pics. I may have the 7402 chip reversed on the bottom. Can anyone confirm?

Yep. IC8 is installed backwards. Pin 1 should point to the side towards the relay.

#19 3 years ago

JKA

JohnnyPhantom

Pinside member