williams system 11b problem

[pinball-collector]

hello all hope all is well,, had a problem with my police force, had low voltage on the power supply board, was a number of things,, anyways,,brought a new power supply from rotton dog,, plugged it in,,straight away, it blew the F3 F1 and F2Aon the Auxiliary board, the l hear some light hiss,, just about cooked the 3 main chip located under the led's on the cpu,, so what the f#@ks going on? to much voltage? my multimeter shit it self,, the new PS board showd 5 V and +12 volts, that was 15 volts, so untill l get a new meter,, so where do l start? any ideas??

[Steevsee]

This is from http://www.pinrepair.com/sys11/index1.htm#coils

Diagnosing a Blown Solenoid Fuse.
If any of the game's solenoid fuse(s) blow immediately at power-on, here's some things to check:

    * First check the pop bumpers and slingshots to see if their "activation" switches are stuck closed (the switches that the ball triggers to make the bumper work). Prior to Big Guns and pre-System 11B, these "special solenoids" are unlike other coils in the game in that if their activation switch is stuck closed, it will keep the coil turned on (or will "machine gun"), and the fuse will blow.
    * With the game off, use a DMM and check the ohm reading of each and every coil in the game. On two lug coils just put the meter leads on the coil's lugs (on three lug coils there is a "common" lug, measure the resistance between the common lug and the other two lugs). All coils should be 2.5 ohms or greater. If a coil is less than 2.5 ohms, the coil is bad and essentially a dead short, hence causing the solenoid fuse to blow.
    * If the flipper solenoid fuse is blown, this is most often a bad or mis-adjusted EOS (End of Stroke) switch. See the flipper section for help with that.
    * If a coil is less than 2.5 ohms, there is probably a reason this happened - the coil locked on, heated up, and melted the insulation off the coil's windings. This causes a short between the windings, and lowers the coil's overall resistance. Usually this most often due to a shorted driver transistor which keeps the coil energized while the game is powered on.
    * For all coils found with less than 2.5 ohms of resistance, disconnect the wire(s) from one of the coil's lugs. For a two lug coil, there is a power wire which is usually a thicker wire or often two thicker wires. This brings power to the coil and is connected to the coil lug with the banded side of the diode attached. The other coil lug has the return wire which goes to the CPU board. I remove the thinner return wire because it is easier, but removing either will disconnect the coil from the circuit.
    * Power the game on with a new solenoid fuse. Does the fuse still blow? If not, you have found the start of your problem (the bad coil - now you need to find out what made the coil bad!) If the fuse still blows, look for another bad coil or perhaps a short from the coil voltage to ground.

[Skybeaux]

Rottendog do make some very good boards , but the power supply's for Williams and Data East games arn't one of them.
The reason they are inexpensive is because they are made cheap.
I had a Lethal Weapon to repair not long ago with display problems , lighting up too many pixels.
The owner had bought a brand new Rottendog power supply for it recently along with a cpu board.
The voltages coming out of the power supply were wrong and where it should have been giving out +100 volts it was giving out +140 volts!!!
I sold them a good rebuilt original power supply and all is well now.
Extremely lucky no damage was done to the display , i got them to send the board back and get their money back.
I also read of a couple of other people having problems with them on RPG

Get a new multimeter and check the voltages from the power supply with no other boards connected to make sure they are right.
Sounds like you've done a bit of damage to your boards.

[pinball-collector]

This is from http://www.pinrepair.com/sys11/index1.htm#coils

Diagnosing a Blown Solenoid Fuse.
If any of the game's solenoid fuse(s) blow immediately at power-on, here's some things to check:

    * First check the pop bumpers and slingshots to see if their "activation" switches are stuck closed (the switches that the ball triggers to make the bumper work). Prior to Big Guns and pre-System 11B, these "special solenoids" are unlike other coils in the game in that if their activation switch is stuck closed, it will keep the coil turned on (or will "machine gun"), and the fuse will blow.
    * With the game off, use a DMM and check the ohm reading of each and every coil in the game. On two lug coils just put the meter leads on the coil's lugs (on three lug coils there is a "common" lug, measure the resistance between the common lug and the other two lugs). All coils should be 2.5 ohms or greater. If a coil is less than 2.5 ohms, the coil is bad and essentially a dead short, hence causing the solenoid fuse to blow.
    * If the flipper solenoid fuse is blown, this is most often a bad or mis-adjusted EOS (End of Stroke) switch. See the flipper section for help with that.
    * If a coil is less than 2.5 ohms, there is probably a reason this happened - the coil locked on, heated up, and melted the insulation off the coil's windings. This causes a short between the windings, and lowers the coil's overall resistance. Usually this most often due to a shorted driver transistor which keeps the coil energized while the game is powered on.
    * For all coils found with less than 2.5 ohms of resistance, disconnect the wire(s) from one of the coil's lugs. For a two lug coil, there is a power wire which is usually a thicker wire or often two thicker wires. This brings power to the coil and is connected to the coil lug with the banded side of the diode attached. The other coil lug has the return wire which goes to the CPU board. I remove the thinner return wire because it is easier, but removing either will disconnect the coil from the circuit.
    * Power the game on with a new solenoid fuse. Does the fuse still blow? If not, you have found the start of your problem (the bad coil - now you need to find out what made the coil bad!) If the fuse still blows, look for another bad coil or perhaps a short from the coil voltage to ground.


Thank you very much for that lmfo,,lm sure its a voltage problem,,will check that first, to make sure its ok,,,,

[pinball-collector]

Rottendog do make some very good boards , but the power supply's for Williams and Data East games arn't one of them.
The reason they are inexpensive is because they are made cheap.
I had a Lethal Weapon to repair not long ago with display problems , lighting up too many pixels.
The owner had bought a brand new Rottendog power supply for it recently along with a cpu board.
The voltages coming out of the power supply were wrong and where it should have been giving out +100 volts it was giving out +140 volts!!!
I sold them a good rebuilt original power supply and all is well now.
Extremely lucky no damage was done to the display , i got them to send the board back and get their money back.
I also read of a couple of other people having problems with them on RPG

Get a new multimeter and check the voltages from the power supply with no other boards connected to make sure they are right.
Sounds like you've done a bit of damage to your boards.

yes l agree,,will get a good MM first and check the voltage,,l did read the forums, after l posted here,,and other people have had problems , with the power supply boards,,hope l haven;t screwed my CPU,,,l bet the PS is putting out to much voltage,,

l shits me,,just about every thing you buy now, is rubbish,, thanx for your reply.

[beaky]

if you still have the old power supply and you want it repaired just send it up and i will get it running as good as new.

[pinball-collector]

hello,,might have to,, started out with a low 5 volt problem ( .5 volts )....Now, with new board from rottendog,,ended up with blown f1 and f2a fuses on the Aux board and a dead short to connector j15 on the cpu, -18 v,,, but board is showing the right voltage ( PS ) , will put the old board in again, and check again.

[beaky]

I have a couple of system 11b pins here so i can test boards before and after they have been repaired. I have recently rebuilt a power supply for a zaccaria & sega. also i have rebuilt quite a few boards over the years. I will have a look at the police force schematics and see if i can offer you some advice over the next day or 2.