(Topic ID: 314838)

Bally SBM and 6MDM - No playfield controlled lights - Solved

By MrCleanHead

1 year ago


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#1 1 year ago

Well, Im at a loss here. I have been trying to bring back a Silverball mania back to life. I decided to just buy new boards since it was not much more than rebuilding the old boards with the upgrades. I bought weebly boards (MPU, Solenoid driver, sound and lamp driver). BEFORE I installed them I rebuilt the rectifier board. It was blowing the 10A fuse. Found that someone tied in the blue wire to the orange wire (Braided bus wires) under the playfield causing the fuse to blow. There was also a added wire from the left spinner - 1000 when lit to the the upper left Spot letter when lit lamp. I also removed that. No more blown fuse and all voltages are correct. First I installed the Solenoid driver board and checked voltages, all good. Then I installed the MPU and lamp driver board. Game boots up like it should. I then installed the sound board and all new displays (LED), awesome I can play a game It plays fine, ran through the test modes (switch and solenoid test fine) but I just had GI and a few locked on lights. So, I know I have new boards so I re-pinned the connectors that looked bad, they looked pretty good but did it anyways. Same result. I then started to look for some more hacks under the playfield, pulled all lights and check everything with my DMM. I dont see anything touching something that it shouldnt and didnt see any other hacks. On the back box my Same player shoots again, match and 2nd and 3rd "L" dont light. In test mode the rest flash as well as some controlled lights on the playfield but just the B,R,E,L,L by the stand up targets. The rest will not light in or out of test mode.

One thing to note: I only plugged one display in at first and took a picture to show a friend. Looking at that pic I did have controlled lights at that time.

So, I happen to have a working 6 Million Dollar man here and plugged in the new weebly lamp board and same thing, no playfield lights - NOW no lights even with the original lamp board. So my there is a problem with the new board and its screwing up the MPU.

First thing is that I need to get the 6MDM back up and running. I swapped out the 6821 chips at U10 and U11 since I had them, no change. This game is also all original hardware.

Any help here would be great for the 6MDM and then we can figure out whats going on with the Silverball mania board killer.

Thanks
Rob

#2 1 year ago
Quoted from MrCleanHead:

First thing is that I need to get the 6MDM back up and running.

In lamp test mode can you tell us *all* the lamps that are not working or if it's easier the lamps that are working. Let's see if there's a pattern to the behavior in lamp selection.

#3 1 year ago
Quoted from Quench:

In lamp test mode can you tell us *all* the lamps that are not working or if it's easier the lamps that are working. Let's see if there's a pattern to the behavior in lamp selection.

On the 6MDM: Upon start up, in attract mode, only the Shoot again light is lit (locked on) on the playfield, no attract pattern (also pops are on, they may always be on?) Back box looks to be working as should. In test mode, no lights flash at all and shoot again light is off (pops dont flash but are on), backbox controlled lights flash as they should.

#4 1 year ago
Quoted from MrCleanHead:

Upon start up, in attract mode, only the Shoot again light is lit (locked on) on the playfield

What's the Same Player Shoots Again lamps on the backbox doing? Are they stuck on too or off?
Which lamp driver board are you currently running in it?

Are you measuring 6VDC on the braided wire running to the base of all the other controlled lamp sockets on the playfield?

#5 1 year ago
Quoted from Quench:

What's the Same Player Shoots Again lamps on the backbox doing? Are they stuck on too or off?
Which lamp driver board are you currently running in it?
Are you measuring 6VDC on the braided wire running to the base of all the other controlled lamp sockets on the playfield?

6MDM: The same player shoots again lights come on but are very dim, if you had the glass on you would not see it. I have the original Bally lamp driver board in this game. Im only getting ~.9VDC on the playfield (braid to cabinet ground, I think thats right) and ~3.8VDC across stuck on shoot again lamp. I checked the fuses and they are good, then I checked voltages at the rectifier board and they check good as well.

#6 1 year ago

Not a big fan of throwing new boards in a pin without doing some basic troubleshooting.

With the MPU unplugged are the lamps off and do they light when you ground their wire tabs?
Next, check the new B&I MPU switch setting. Is is set correctly for the game?

Have you measured the voltage on the switched lamp bus? It should be 6.3v DC. If there is any AC present you will have problems.
What is the behavior if you use incandescent laps.

carefully inspect the Buss and make sure there is absolutely no cross between GI and switched lamps.

#7 1 year ago
Quoted from MrCleanHead:

Im only getting ~.9VDC on the playfield (braid to cabinet ground, I think thats right) and ~3.8VDC across stuck on shoot again lamp.

So on the base of the playfield shoot again lamp socket where the braid connects, you effectively measure 3.8VDC with respect to ground (cabinet braid) meanwhile you measure 0.9VDC at the braid connection of a lamp socket base of some other playfield controlled lamp?

The braid wire connecting to all the bases of the controlled lamp sockets should measure 5.4VDC to 6.5VDC. By base of the lamp socket I mean where the socket is screwed to the playfield. This is the controlled lamp power buss source and it comes from the blue wire at connector J1 pin 7 at the rectifier board. It's sounding like you have a bad connection at this pin.

#8 1 year ago
Quoted from BigAl56:

Not a big fan of throwing new boards in a pin without doing some basic troubleshooting

SBM: Agree 100%, before I even had the new boards I inspected the BUS lines since someone jumped them together causing the fuse to blow. I found it and rebuilt the rectifier board, checked voltages and then moved on to the driver board. It was bad as well, MPU was battery rotten and that dripped onto the lamp board. I just checked the BUS lines again and dont see anything crossing over, I have looked at this so much Im going blind and getting dumber I think

Quoted from BigAl56:

With the MPU unplugged are the lamps off and do they light when you ground their wire tabs?

SBM: Where I have lights installed, yes they will come on (new weebly board)

Quoted from BigAl56:

Next, check the new B&I MPU switch setting. Is is set correctly for the game?

Yes, sound board and MPU set correctly (game was working with the new boards and I did play a few games before the problem)

Quoted from BigAl56:

Have you measured the voltage on the switched lamp bus?

6.3VDC but Im also reading 3.4Vac, will all the boards unplugged except the rectified board. I will pull the rectified board again and double check everything and inspect the BUS lines again. Something dont seem right unless Im looking at this the wrong way....

#9 1 year ago
Quoted from Quench:

So on the base of the playfield shoot again lamp socket where the braid connects, you effectively measure 3.8VDC with respect to ground (cabinet braid) meanwhile you measure 0.9VDC at the braid connection of a lamp socket base of some other playfield controlled lamp?
The braid wire connecting to all the bases of the controlled lamp sockets should measure 5.4VDC to 6.5VDC. By base of the lamp socket I mean where the socket is screwed to the playfield. This is the controlled lamp power buss source and it comes from the blue wire at connector J1 pin 7 at the rectifier board. It's sounding like you have a bad connection at this pin.

6MDM: Yes, when I have the DMM hooked up upon start up I get 6.3V, right after it boots it drops to ~.9VDC

This game was fully working until I put in the new lamp board from the Silverball Mania, apparently that game has messed up the board or the board failed and me trying to isolate the problem now messed up the 6 million dollar man...

#10 1 year ago
Quoted from MrCleanHead:

Yes, when I have the DMM hooked up upon start up I get 6.3V, right after it boots it drops to ~.9VDC

Just confirming you are measuring the base of the lamp socket as indicated below.

Right now I suspect the lamp driver board has nothing to do with your current problem because it cannot cause the playfield lamp buss voltage to drop from 6.3V to 0.9V (without affecting the backbox controlled lamps).
It just sounds like a typical playfield harness J1 pin 7 connector issue at the rectifier board considering the backbox controlled lamps are working.

Lamp_Socket_Controlled.pngLamp_Socket_Controlled.png

#11 1 year ago
Quoted from Quench:

Just confirming you are measuring the base of the lamp socket as indicated below.
Right now I suspect the lamp driver board has nothing to do with your current problem because it cannot cause the playfield lamp buss voltage to drop from 6.3V to 0.9V (without affecting the backbox controlled lamps).
It just sounds like a typical playfield harness J1 pin 7 connector issue at the rectifier board considering the backbox controlled lamps are working

Correct, I pulled the transformer (6MDM) to check it and compare it to the SBM one. They compared the same. Reinstalled it in the 6MDM and now it works. 6.3V before and after boot up. I guess I will re-pin that one as well later today.

Now, as far as the Silverball mania goes. I have a steady 6V on the backbox and the playfield BUS line. The game plays fine except for the controlled lights (same as reported previously). I have some lights stuck on but most are out (all center playfield lights). Nothing blinks in attract mode. I have re-pinned J2, J3 and J4 on the MPU board and new pins and headers on the rectifier board (before I got the new boards). I will do the same for J1 and see if that fixes anything here shortly and report back.

#12 1 year ago

Did you repin the 0.100 connectors to the LDB?

#13 1 year ago
Quoted from Billc479:

Did you repin the 0.100 connectors to the LDB?

Working on it Getting old sucks and I can only lean over the game for so long Plus I hope I dont run out of pins...

#14 1 year ago

You probably had a connector crimp snap off if the issue started after swapping boards. LAMP STROBE being open circuit will stop all feature lamps from functioning. Missing address/data can result in wrong/missing lamps.

#15 1 year ago
Quoted from barakandl:

You probably had a connector crimp snap off if the issue started after swapping boards. LAMP STROBE being open circuit will stop all feature lamps from functioning. Missing address/data can result in wrong/missing lamps.

You would be correct. After changing out all the pins on the MPU J1 and all pins on the LDB J4 and J2 all my lights except 3 have came back. I will re-pin J3 and J4 once I get more pins. I have fixed many of these Bally/Stern pins and have never ran into this. Probably just got lucky and/or the age of the games are creeping up fast. Plenty more games to fix, hopefully I dont run into this to often or at all.

Thanks for the help guys!
Rob

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