Gottlieb SS Sinbad Help *SOLVED* partially...

[urbecrisch]

To summarize:

Got a SS Sinbad pin at an auction 2 years ago.  Needed some work, thought I could do it myself but I couldn't so I took pin to a reputable pin guru in the area.  Was told I needed major work done on the CPU board so I made it easy on him and bought a Ni-Wumpf replacement board.  He installed the CPU and the pin has been playing flawless for 1 1/2 years until...

Last weekend my family were over and the game was on for a few hours.  All of a sudden when I pressed the start button (on freeplay) nothing happened.  I opened the backbox and noticed a broken wire on A1-J6 on the CPU board.  I shutdown the game and ordered some new crimp terminals (.156") for the A1-J6 connector.  Yesterday I replaced the terminals and inserted the connector and turned on the machine.

The lights turn on, the display works, but I do not get any sound from my chimes and when I push the start button the game does not start.  I ran a coil test from my Ni-Wumpf CPU and all pass except my Knocker, and the 3 other chimes.  I'm not sure where the problem lies.

I checked the other connectors on the Power and Driver boards but all seem intact.  I also checked the TILT switch and Slam Switch but those are OK too.  Not sure if this is a Driver Board issue or something related to the CPU however the CPU is a Ni-Wumpf and is only 1 1/2 yrs old.  I want to try to fix this problem myself before I look elsewhere and I don't want to haul the machine to someone so if I cannot fix it I think I'll be making a house call.

So any thoughts or suggestions on how to move forward with this?

[urbecrisch]

Well, I was able to get the pin working...temporarily.  I was on pinrepair.com going through some troubleshooting and I came across this:

"A Common Switch Matrix Problem.
Because system1 games do not have a free-play setting, users often press the coin switches inside the coin door with their fingers to add credits. This is fine, but while doing this often the user will move the "lock-out wire" so it touches one of the coin switch blades. This will short that return/strobe switch matrix line to ground, making the game freak-out. Usually a game won't start, or there will be some other strange game behavior. The game may not even boot, or may act like it is always tilted or slam tilted."

Sure enough when I turned the game on and hit the coin switch with my finger I got chime sound and the game started, however;

I played some practice games and at times it seems when the ball strikes a drop target or rollover target, the flippers and chimes stop working.  If I turn the game on/off it works again but the problem sometimes occurs again.  Not every game but enough to know there is some sort of issue.  Is this a grounding problem?  I didn't have to do the CPU grounding modification suggested with Gottlieb System 1 games cause I had a Ni-Wumpf board installed.  Is there another way to check if this is a grounding problem or can anyone think of another issue I may be having?

[urbecrisch]

Did you repin your connectors?

A1-J6 connector to the CPU was re-pinned last Saturday. 

Seems more like a grounding issue but I'll also re-pin/check the power supply and tilt connectors. 

Should I still mod the ground on the Ni Wumpf or ground the power supply and driver board and bypass grounding the Ni Wumpf ?

[shardian]

Should I still mod the ground on the Ni Wumpf or ground the power supply and driver board and bypass grounding the Ni Wumpf ?

Why is there a debate?

[urbecrisch]

Why is there a debate?

I recently read somewhere that if you ground the driver board and power supply that you would not need to ground the CPU.  Will have to find that quote, it was from a forum somewhere who contacted Ni Wumpf and said it was not necessary if the other two were grounded.

Much easier to just ground the CPU but that is why I asked.