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MILLIONAIRE (Williams System 11a, 1987) Wouldn’t start, this turned out to be due the a missing pinball in the outhole. The game started but The flippers didn’t work! This turned out to be due to a blown fuse… and a pulled wire on the flipper driver section. Maybe purposely unplugged. Now that the flippers work I noticed that the game never really kicked the ball from the outhole onto the plunger tip. The switches passed the test. I checked the switches with the diagnostic test and they were set right. But now I see the solenoids, the first 9-10 don’t fire at all. This included the outhole kicker the right and left slingshot and so on. I traced the problem to a relay. I took out the relay and all seamed to test okay. Here, I had to understand how this A/C relay worked. So I dug out Marvin fix-it guide, mainly since the system 11a schematics didn’t show playfield parts and underneath PC boards. Looking at the other relays made this more confusing. That is comparing the wiring scheme. There was some heavy solder on the contacts. And there was two red wires, the same thickness going to the same lug on the A/C relay PCB. So here we have the other lug empty, nothing connected to it. I noted at this point from Marvin's fix-it guide that this relay also controls the flashing GE 89 bulbs. Which I noticed don’t work. Here’ the way it was wired:
SO the empty GND lug should be a problem, but what goes there? I can’t see another wired hanging lose or the stump of one cut off. Interesting when I did some switching I lost the upper solenoids to gain the lower. But still didn’t get the bulb flash. Closer look at the diagram show the +28 volt line bridged to both the GND and +28. So both red wires connected to a bridged +28 and GND lug. This fixed it! Now even the flashing lites worked! I see what happened here was that the other technician must have had no diagram. Or he didn’t pay attention to it, and got scared seeing one lug ground and one +28. After all who could comfortably connect the two red wires to the lugs in a normal case. I wouldn’t unless I was sure. The PC board is clearly marked wrong. Wait! The outhole kicker still doesn’t work! Now I tested the coil, okay, somehow okay, it was sticking, needed major cleaning on the assembly. Then it was okay. Here I could test it by ground the non hot side of the coil to the side metal rail confirming it connects all the way to the board, ground the transistors metal tab also fired it. The transistor was bad! A TIP122 Darlington driver. Ah Some art/Cosmetics stuff: There was a Mylar piece where the ball would drop off of the left metal guide/ramp. This piece came off and was no where to be found. The problem there was that it took all the paint with it! It looked like somebody had left a glass there for a year and it ate a perfect ring through the paint to the wood. Here is where I retouched the playfield, with a liner brush and black acrylic paint. The cabinet was flaking badly as well especially one side, and I retouched it as well. 6 months later : ( We moved into a new house good, because now I have more storage space than I need, Bad news is one pin wouldn’t fit through the walkout basement door so I left it out in the garage since January, only lately bringing it in. (I had to remove the head piece) So now when I started the machine after a full wire check, GI lights came on, but no LED flashes, nothing! Uh oh! I smell a resistor burning! It turns out under the playfield not one, but two resistors were burning! Damm! What damage did some cool weather bring in? The Resistors were burnt beyond recognition (or F.U.B.A.R.), these were resistor R$ on each of the two drop target Opto sensor boards.
` Oddly, the part of the board connected to the switch matrix fried the resistor and the same exact one on both, simultaneously cooking at the same time! I unplugged the right connectors, mainly the ones running to the playfield and the burning of course stopped. I found that some schematics I got online didn’t show what resistor R4 was, and that the power supply, (a suspect) was not shown in that schematic set!. A called to Marco specialties, time to get the whole game book. For these two reasons mainly. Now for some voltage tests. Something is wrong with the 12 volts reading which is what as shown to power the opto switch board. But it doesn't’ show high. One of the bridge rectifiers are out. Hmmm. Looks Like I need to fully test the power supply board. But I really want to know why the hell those resistors burned out. Did one of many connectors lose conductivity over the winter? The schematics may help trace that better. I went testing the power supply safely plugged in. In correct readings at the 12v +/- sides. I also find that BR2 has a diode out. Replaced. BR1 does as well. BR1 is PC mounted, soldered on both sides. And a bitch to remove since it is hard to get the solder hot enough to pull it from the board. This unit tends to absorb the heat so it was hot still though not much in melting solder, even with a 75 watt gun. I didn’t want to damage the board so enough of the extreme heat. So I used some cutters to cut off the part then heated up and pulled each pin out. Pretty well need to be sure you don’t want to use it again when you do this. But… I had decided that it needs a heat sink, plus it is to hard to test mounted on the Power supply PC board, and, to hard to replace. So I opted to make it like the other two. That is mount it on the cabinet back in the row with the others. I ran color coded wire 14 gauge, and added crimped on Lug tabs at the ends so that the soldered wires could simply run to the BR1 bridge and connect using these solderless lugs.
Had to drill a hole and that steel plate is a tough one, this is a way to find what drills are not all that sharp. I don’t work with metal much, mostly wood, and aluminum. I applied some heat sink cream to the back and mounted it as shown. (shown at the far right)
Well the schematics tell what the parts are on the Opto board but there is no schematic. So I learned that I need a 820 ohm resistor ½ watt, I replaced these, but did not put the drop target assembly back together just yet. Hard to tell in circuit if the opto board had more problem which I suspect it did. The question is was it due to the power supply problem? So now it boots up but these resistors start to burn AGAIN! Disconnected the 12v+ wire on both. All is still okay but no smoking of course. Apparently the IR led of the opto is shorted and shorting the 820 ohm resistor to ground. How did that happen? Best I can recall is that it was in colder winter weather in the garage, maybe the materials broke down in the cold. Oddly both boards have the same problem. I may look at the whole switch ,matrix to make sure it isn’t out all across that row or column.
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