1 PF bulb is staying on (Gottlieb Arena)

vintagegamer

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The "P" butb is staying on. There is a rollover target near it, but the switch is not closed so I am not sure what is keeping it constantly powered.

Any thoughts? Just crazy that ONE BULB keeps goin!! It also does not flicker like the others during attract mode, just always on.

Thanks!
 
FYI Pinwiki for your GTB 80b game says this:

5.12.4.2 Lamp(s) Will Not Turn Off

If a single lamp is involved, or only a handful of lamps with different lamp device select signals, suspect the lamps' associated drive transistors. If a group of four lamps will not turn off, and they are all controlled by the same 74175, suspect the associated 74175 or the device select for that 74175 ("DS" on the schematics). If numerous groups of four lamps will not turn off, suspect the associated 7404 on the CPU board.
  • Z17 for DS1-DS5 device select signals or,
  • Z24 for DS6-DS11 device select signals or,
  • Z26 for DS12-DS16 device select signals.
If the lamps involved originate from more than one group of device select signals, suspect the 74154 at Z25 or, backing up one more step, the 6532 RIOT at U5.

 
Scucci shared the following:

Looking at the manual, the "P" rollover light is L45, driven off of a flip flop at Z12 (pin 7) through R46 and Q46 (an MPS-U45, probably your issue) on the driver board (A3). Got a feeling Q46 is shorted.

That said, those details are excellent, but my machine now has a Rottendog driver board in it. The board is brand new, so I can't believe this happened within 2 weeks of installing it!!

I've reached out to see if the warranty might cover this, but in the meantime I'm assuming the worst and have ordered new transistors in the event that I need to do surgery. I'll just need to figure out which transistor on the RD board is bad without a schem (none came with it).
 
Scucci shared the following:

Looking at the manual, the "P" rollover light is L45, driven off of a flip flop at Z12 (pin 7) through R46 and Q46 (an MPS-U45, probably your issue) on the driver board (A3). Got a feeling Q46 is shorted.

That said, those details are excellent, but my machine now has a Rottendog driver board in it. The board is brand new, so I can't believe this happened within 2 weeks of installing it!!

I've reached out to see if the warranty might cover this, but in the meantime I'm assuming the worst and have ordered new transistors in the event that I need to do surgery. I'll just need to figure out which transistor on the RD board is bad without a schem (none came with it).
I would try to return the Rottendog board. That company is awful
 
Well I definitely don't want to take advantage of them if it were something I personally did wrong, but I really don't know what I could have done by just switching out a bad bulb :(
 
Thought I made some progress on troubleshooting today but weird: the lamp is L45 that has the issue. I noticed numbers on the RD board and thought Id find L45 but not seeing it... wondering if it might be on the back?20250710_134200.jpg20250710_134206.jpg
 
So here's the latest:

Removed RD board, reinstalled OEM driver board, everything works 100%.

That said,

1. there's obviously a bad component on the RD board
2. I've sent 2 msgs to RD and am awaiting a reply.
3. They never sent me a schem

Do I try to fix it? Wait for a reply from them first? I'd have to test the dang thing blind. Thoughts, pls.
 
So here's the latest:

Removed RD board, reinstalled OEM driver board, everything works 100%.

That said,

1. there's obviously a bad component on the RD board
2. I've sent 2 msgs to RD and am awaiting a reply.
3. They never sent me a schem

Do I try to fix it? Wait for a reply from them first? I'd have to test the dang thing blind. Thoughts, pls.
You are unlikely to get a reply from them. Did you buy it directly through them or a 3rd party site like Marco? If you bought it directly through them you are screwed due to poor communication. If through a 3rd party site you should be able to talk to someone and get your money back. They make junk products and do not support them. Sorry you fell for it.

I have to ask why you even changed the board in the first place if it was working. If you want to try to fix the Rottendog board, that may void the warranty, but you can try to figure out what pin is associated with that light and trace it back on the board to the relevant component. Check against other known good components in similar circuits.
 
The "P" butb is staying on. There is a rollover target near it, but the switch is not closed so I am not sure what is keeping it constantly powered.

Any thoughts? Just crazy that ONE BULB keeps goin!! It also does not flicker like the others during attract mode, just always on.

Thanks!

This thread is the same as this one you made about the same issue?


And I did provide a board schematic in your other thread.
 
Fix this yourself.

Either the transistor is bad, or the logic chip driving that transistor is bad, and that line is stuck high, causing the transistor to be stuck on.

Those transistors/lights are not intended to stay on continuously. They're meant to have some duty cycle, where they are flashed on and off. So that's probably why the transistor is darker than the others, it's just gotten very hot because it's stuck on.

A similar thing happens on Sea Wolf boards. If the game board locks up, a bunch of the lights get stuck on, and it blows the transistors that drive them. In that case the transistors are so small they can't handle being stuck on at all, and they melt in a few seconds. On that RD board, it looks like they are using beefier ones, that maybe can handle a continuous duty cycle. But they are still going to get pretty hot.)

I'd replace the transistor first. And if that doesn't fix it, replace the HCT175. (Or you could replace the 175 first, either way.) You might be able to test the transistor with power off, and compare it to the adjacent ones, to see if it's bad, before replacing anything.

You'll need desoldering tools. If you don't have any, now is a good time to invest in some, and learn. Replacing those two parts is relatively easy, and will save you from having to deal with returning the board.
 
Fix this yourself.

Either the transistor is bad, or the logic chip driving that transistor is bad, and that line is stuck high, causing the transistor to be stuck on.

Those transistors/lights are not intended to stay on continuously. They're meant to have some duty cycle, where they are flashed on and off. So that's probably why the transistor is darker than the others, it's just gotten very hot because it's stuck on.

A similar thing happens on Sea Wolf boards. If the game board locks up, a bunch of the lights get stuck on, and it blows the transistors that drive them. In that case the transistors are so small they can't handle being stuck on at all, and they melt in a few seconds. On that RD board, it looks like they are using beefier ones, that maybe can handle a continuous duty cycle. But they are still going to get pretty hot.)

I'd replace the transistor first. And if that doesn't fix it, replace the HCT175. (Or you could replace the 175 first, either way.) You might be able to test the transistor with power off, and compare it to the adjacent ones, to see if it's bad, before replacing anything.

You'll need desoldering tools. If you don't have any, now is a good time to invest in some, and learn. Replacing those two parts is relatively easy, and will save you from having to deal with returning the board.
they might be MOSFETs. I had to fix multiple Rottendog boards from Gottlieb Premier games. @VidyaGamez speaks the truth. I had a MPU327-4 go bad on Firepower and they were like "durr maybe the CPU is bad" and I told them again I tested all the socketed chips and they're all good and they just stopped talking to me. so I wound up sourcing original boards and Firepower is manlier now.

if they're MOSFETs you do a resistance check across the outer legs and it should read something like 13k ohm. if it's way lower than that the MOSFET is bad.

likewise, I'll ask why you spent the money on an expensive Rottendog board if your old board worked. lol
 
they might be MOSFETs. I had to fix multiple Rottendog boards from Gottlieb Premier games. @VidyaGamez speaks the truth. I had a MPU327-4 go bad on Firepower and they were like "durr maybe the CPU is bad" and I told them again I tested all the socketed chips and they're all good and they just stopped talking to me. so I wound up sourcing original boards and Firepower is manlier now.

if they're MOSFETs you do a resistance check across the outer legs and it should read something like 13k ohm. if it's way lower than that the MOSFET is bad.

likewise, I'll ask why you spent the money on an expensive Rottendog board if your old board worked. lol


Yeah you're correct, they're FETs. (Sorry, I was being lazy with my terminology.)

The nice thing about comparative measurements is you don't have to care that much. You just want to see if it measures significantly differently from adjacent ones that do the same thing.
 
Yeah you're correct, they're FETs. (Sorry, I was being lazy with my terminology.)

The nice thing about comparative measurements is you don't have to care that much. You just want to see if it measures significantly differently from adjacent ones that do the same thing.
yeah, I had nothing to work off of when one of the slingshots (or I think they call it "kicking rubber") was stuck on Surf'n Safari, I literally tested every single one on the board until I found the bad one lol. and then Strikes n Spares had something sticking on, blowing fuses, had to change like 3 or 4 of those. alas, I got both games to work and all was swell. I might even have the pictures from when I worked on them, just don't remember if it was 2021 or 2022.

I honestly didn't know shit from apple butter about pinball in my first run here.
 
This thread is the same as this one you made about the same issue?


And I did provide a board schematic in your other thread.

Yes, I tried to get this over into the repair section for further review by all, but folks continued to post in this one as well.

This is the one in the repair section, but I greatly appreciate all of the help everyone has been sending!!

 
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