Continuing on with my summer of projects.... I picked up this Tee’d Off last week completely dead. The main fuse holder was broken so after replacing it the game fired up. However, none of the control lamps work. I looked over the connections and checked the fuses. None of them were bad. It appears that there is power to the lamps. I’m not great with gottliebs (I’m actually pretty amateur at all pinball repair lol) so I have no idea where to even start. Any help would be greatly appreciated.

Bump to the top for any ideas?

I do have both of those. I am not really sure how to use it lol. I will look over the schematics. I don’t understand when it should read high or low. I’ll read up some on how to use it more and start checking. I didn’t even think about it being in the cpu I was looking over the driver board. Sounds like our boards had very similar issues

So I am not very good at this but I traced the lamp matrix back to u4 on the cpu. It looks like pins 10-12 control it. I used the logic probe and got the following readings:

Pin 10- low
Pin 11- high
Pin 12- high

I’m not sure how I am supposed to know what they should be. Is there a way to tell from this schematic if it should be low or high (reiterating not being very good at this lol)

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Pins 2,5,6,7,8 read high/low

Pins 3,4,9 read high

Pins 26-33 all read high/low

I really do appreciate the help

Pins 13,14,40 are all low

I’m not sure. I am attaching some pics of the schematic if that helps.

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F4384C02-39A2-497C-A652-2806A70D9340 (resized).jpeg

Yes there is one. I checked it outside of the game with a meter and then went ahead and replaced it anyway just to be certain that wasn’t it.

Were you ever able to get the stargate up and going? Marco has those chips in stock if I need to replace them. I need a pop bumper smart switch so I’ll be ordering from there anyways but I don’t really want to just shotgun replace them if they aren’t the culprit. I do not like the solder pads on Gottlieb boards as much as others... plus they are $10 a piece lol

No problem. Hopefully you get your figured out easily. I went ahead and ordered the chips just cause I was ordering other stuff and didn’t want to make two orders.

So... I just went ahead and replaced u4 cause it was sitting here and I thought why not.... The result was the same. I also checked a different ribbon cable between the mpu and the driver board just to be safe but also no change.

I have 4.84vdc on pin 3 and 1.56vdc on pin 11

Bumping this to the top. Anyone got any ideas?

Awesome thanks. I’ll start reading through it today

Could this be caused by a ground issue? The game does not have any ground mods completed on it. Each lamp column lights when I short the corresponding IRL on the driver board which makes me think (like you previously have suggested) that it is definitely an MPU issue so I at least feel like we are moving in the right direction. U4 and U5 have both been replaced with new 6522 chips. u19 and u20 are both showing 5vdc at pin 3 but both shsow some mv at pin 12 instead of 0v.

At this point there are no stupid suggestions. When I shorted the transistors on the board the control lamps lit up. I am pretty sure that all of them lit up.

I haven’t had a chance to work on any pinball machines in the last couple of months. I am still open to any ideas that anyone has.