Williams System 6 Blackout Lock-on

[HHaase]

Yeah, I did change out the 40 pin interconnect. Per the repair articles, I've only replaced the female end as the male end looks fine to me.

I'd have to check again, but I think that when I tried the legs of the PIA, 17 gave a reading of ~4V. The other pins 2 - 16 were low.

That's exactly what you're looking for when you're in attract mode from the PIA. All the playfield coils are off, and the coin door interlock is on. It's a good thing to see. Though if you have locked-on coil problems come back, check it again to see if anything changed. Do this with the coils unplugged from the drive board, so you don't risk burning anything, it won't affect the test.

In case it got lost in the shuffle, also make sure to do new connectors on the 5v logic power both on the power supply and on the CPU board side. I'd highly recommend a power supply capacitor kit, but GPE's sold out and it won't be until October until he gets more of the 12,000 axial lead capacitors, and that's the important one.

-Hans

 

[vipe155]

That's exactly what you're looking for when you're in attract mode from the PIA. All the playfield coils are off, and the coin door interlock is on. It's a good thing to see. Though if you have locked-on coil problems come back, check it again to see if anything changed. Do this with the coils unplugged from the drive board, so you don't risk burning anything, it won't affect the test.

In case it got lost in the shuffle, also make sure to do new connectors on the 5v logic power both on the power supply and on the CPU board side. I'd highly recommend a power supply capacitor kit, but GPE's sold out and it won't be until October until he gets more of the 12,000 axial lead capacitors, and that's the important one.

-Hans

So are you suggesting that the PIA is still good?

It's great that the coils aren't locking on anymore; not so great that something happened and now there are no coils.

 

[HHaase]

From that test, the PIA was working properly when you tested it.

Are you getting voltage to the coils? With the game powered on, you should be seeing 28v or more on all the coils at all times. They are always powered, and get switched via turning the ground on and off. If no voltage, check the fuse first.

-Hans

 

[vipe155]

Ok, I checked the solenoid power at 3J3 and no 28V. The fuse F2 is blown. What does that mean? Should I just put a new fuse in, or is this a sure sign something needs to be addressed first?

 

[HHaase]

If the PIA is checking good still, I'd put in a new fuse. But keep you hand close to the power switch, as you'll want to shut it right down if a coil locks on again.

IF a coil locks on again, then pull that fuse, and run the PIA test again and see if it changed. If a coil locks on, and the PIA checks good, it's time to move on to testing other chips. But it matters which coil it is if you can spot it quickly.

-Hans

 

[vipe155]

I just looked at the F2 fuse I pulled out, and it says it is a 15A 32V fuse. Shouldn't it have been a 2.5 amp slo blo?

 

[HHaase]

I just looked at the F2 fuse I pulled out, and it says it is a 15A 32V fuse. Shouldn't it have been a 2.5 amp slo blo?

Yep. And that is why your whole problem started with a locked and fried coil, instead of a locked coil and blown fuse. Likely the previous owner had the same locking coil problem, and used this as his "Fix". Stick with the 2.5amp slow blow's, or be prepared for more melted coils in the future.

When I picked up my Black Knight I found a 25 amp circuit breaker clipped into the same spot...... and 2 fried coils.

-Hans

 

[Lindsey]

Yep. And that is why your whole problem started with a locked and fried coil, instead of a locked coil and blown fuse. Likely the previous owner had the same locking coil problem, and used this as his "Fix". Stick with the 2.5amp slow blow's, or be prepared for more melted coils in the future.

When I picked up my Black Knight I found a 25 amp circuit breaker clipped into the same spot...... and 2 fried coils.

-Hans

That's how some techs "find the problem". Up the amperage of the fuse until something blows up. Ugly but I've seen it happen way too many times.

Breakers modified to plug into fuse holders are good to have around but I pride myself on blowing the least number of fuses possible. It's pretty rare in solid state games that you'll need to go through a bunch of fuses to solve a problem. EMs can be a different story. Fuses are something that's easy to overlook with a "new to you" game.

 

[vipe155]

That's how some techs "find the problem". Up the amperage of the fuse until something blows up. Ugly but I've seen it happen way too many times.

Breakers modified to plug into fuse holders are good to have around but I pride myself on blowing the least number of fuses possible. It's pretty rare in solid state games that you'll need to go through a bunch of fuses to solve a problem. EMs can be a different story. Fuses are something that's easy to overlook with a "new to you" game.

Well, I put a new 2.5 amp slo-blo fuse in. When I turned the game on, there was quick little blue "flash" in the fuse, and still no solenoids. I assume it's blowing that F2 fuse on power on then?

So, I just tried something else. I disconnected the new coil I installed (it replaced the original one that burned up) and now the machine powers up with some solenoids working. I tested the 3J3 power again, and I'm getting 37V according to the DMM from the solenoid power.

 

[HHaase]

Wouldn't be a power supply issue, though wouldn't hurt to test the 32v rectifier just in case. I would still be looking at the driver board.When you saw the flash, did you also hear a big clunk from the playfield? PIA still showing the same on pins 2-17?

For now, leave the blown fuse in there. If the PIA is still checking good, we're moving on to other chips now.

For IC1, IC2, IC3, IC4 With the game turned on (and the blown fuse still there)........
You should see zero voltage on pins 3,6,8,11
This is the output, any voltage on one of these will cause a coil to turn on.

The exception is that IC4 should have voltage on pin 3 because of the coin lockout, this is the pin17 on the PIA that had voltage for you before.

You'll also want to check the special solenoids at IC8 and IC9
Look for voltage on pins 1,4,10,13. You should see zero on these too.

-Hans

Edit: just saw your update about the new coil. Was it wired backwards possibly? The pair of thicker wires should be on the striped side of the diode on the coil, and the single thin wire on the un-striped side of the diode. The coil DOES have a diode on it, correct?

 

[vipe155]

Well you see, when I disconnected that coil I replaced I put a new fuse in, and it didn't blow that fuse. Now the other solenoids (or most of them) seem to work.

 

[HHaase]

Well you see, when I disconnected that coil I replaced I put a new fuse in, and it didn't blow that fuse. Now the other solenoids (or most of them) seem to work.

Hmmm, which ones aren't working (as I've lost track at this point).

On the new coil, did it have a diode on it, and did you have it wired in correctly?
Which coil was it again?

-Hans

 

[vipe155]

Ok, I can feel this getting closer. I really appreciate your help, and I wish I had someone nearby this helpful.

Here is a total status update. I am an idiot. I wired up the new replacement coil according to how the other coils were done. But, it seems the diode on this new coil is opposite the others, so I wired the coil backwards. Therefore, I switched the wires around and it is now correct.

So, I put the fuse back in and powered up the game. I checked the power at the connector, and there was 37V going to the solenoids. Then, I turned the game off and replaced the connector *3J3* As soon as I plugged it in, there was a small spark on one of the pins. Turned the game on, no solenoids. Then I turned the game off.

Now, there is 4V going to the solenoids at 3J3 instead of 37V after the spark.

 

[HHaase]

Don't feel bad, the backwards diodes have stung a lot of people.

Leave 3J3 out for now, and test the transistor for that coil. Chances are it got fried from the backwards diode, also test the 2N4401 pre-driver. Something in the driver board is still drawing current, so I'd still do that test of IC's 1-4 to find out what.

-Hans

 

[vipe155]

Don't feel bad, the backwards diodes have stung a lot of people.

Leave 3J3 out for now, and test the transistor for that coil. Chances are it got fried from the backwards diode, also test the 2N4401 pre-driver. Something in the driver board is still drawing current, so I'd still do that test of IC's 1-4 to find out what.

-Hans

Ok, I did what you said. I replaced the TIP102 on the coil that was wired wrong because it was giving me a low 0.1 diode reading. Then, I put the driver board back in and checked all of the ICs you said (1,2,3,4 and 8 + 9). I got minimal readings (.1 to .2) on the legs you mentioned until IC9. On IC9 pin 10 I got 4V. When I tested it a sound effect from the game played as well.

 

[HHaase]

All looking good so far, not surprised at all that TIP102 is fried. How was the 2N4401 for that coil? It was probably a normal sound that gets played during attract mode, and on the system 6 the driver board did fire off sounds. I don't know which sounds play when on blackout, we'll get back to that later.

Now I'd disconnect 2J12, 2J11 and 2J9 on the driver board, put the fuse back, and see what happens. Then test for voltage on the pins for those connectors if the fuse holds.

-Hans

 

[HHaase]

Sorry, had to take a phone call, slow on the edit this time.

IC9 doesn't control the sound circuits, it controls the left kicker. What do pins 5 and 6 in IC9 say?

Also what about IC7 pins 11,12,13?

Check for a closed switch at the left kicker, don't forget there are two of them there.

-Hans

 

[vipe155]

All looking good so far, not surprised at all that TIP102 is fried. How was the 2N4401 for that coil?

Now I'd disconnect 2J12, 2J11 and 2J9 on the driver board, put the fuse back, and see what happens. Then test for voltage on the pins for those connectors if the fuse holds.

-Hans

The predriver for that coil seemed to test good. Did the connector stuff, and only had some voltage (.7) on pin 7 of 2J9.

IC9 doesn't control the sound circuits, it controls the left kicker. What do pins 5 and 6 in IC9 say?

Also what about IC7 pins 11,12,13?

Check for a closed switch at the left kicker, don't forget there are two of them there.

-Hans

4V & 5V respectively on those pins on IC9, and 4V, 5V and 5V for those pins on IC7. The switches do not seem to be closed on the left kicker.

 

[HHaase]

Bah..... I'm at this too long and starting to screw up. You're right, there won't be a stuck switch on the left kicker. IC9 pin 10 is going to always have 5v due to the design. It's actually the ONE pin on the special solenoids that will always do that. Not sure where my brain was on that one. From the numbers your giving me I'm going to say that both the PIA chip and the logic chips are testing as good.

I hate to keep saying to put new fuses in, as I'm costing you money if I'm wrong, but I'd say it's time to give it a try again with everything connected and a new fuse for the solenoids. If I make you blow many more fuses, I'll send you some.

-Hans

 

[vipe155]

Bah..... I'm at this too long and starting to screw up. You're right, there won't be a stuck switch on the left kicker. IC9 pin 10 is going to always have 5v due to the design. It's actually the ONE pin on the special solenoids that will always do that. Not sure where my brain was on that one. From the numbers your giving me I'm going to say that both the PIA chip and the logic chips are testing as good.

I hate to keep saying to put new fuses in, as I'm costing you money if I'm wrong, but I'd say it's time to give it a try again with everything connected and a new fuse for the solenoids. If I make you blow many more fuses, I'll send you some.

-Hans

Ok, I put my last 2.5A fuse I had laying around in the game. It started up with no locked on coils, and I ran the coil test and it went through that with pretty much everything working. Overall, it's getting there.

The start button still does not work. I could not start a game with it or adjust any values in the adjustment area. I tried adding credits on the coin door, but those do not. Also, oddly, in the coil test I noticed that the coil I had wired backward is not working. Could it have been damaged from being wired wrong?

It's almost there I think.

Also, I should be the one paying you for all this help, not the other way around. Don't worry about blown fuses or anything.