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ganastas 11-10-2015 06:47 PM

Oops, I think i fried my Black Knight 1980
Hi all,

My machine was running perfect until my move. When I tried and set it up at my new place I hooked everything up except the two large connectors in the head I got mixed up. And there the only two that will engage with each other (square peg round hole thought). Two large white connectors and on the head side one black and one white. Being in a rush I forgot the head end has a black stripe on one of the white connectors. Well I mixed them up and powered it up. Many solenoids locked on then I shut it off. tried it twice again same result. Realizing what I did wrong I corrected the install and powered up. Nothing just a "0" on the mpu no boot. Also noticed top left chip on mpu to hot to touch.

I'm sure this has happened to many other dumb dumbs like myself. As it can happen if you don't pay attention. Any body seen the outcome from this incident before? :cheers:


sleepy 11-10-2015 11:16 PM

I'm not a pinball tech, but I found this:!to...ll/2LP4bqu_VtE

EDIT: The following might not apply to Williams circuits, and is not from the Google Groups link. This is my personal experience.
I had a Yamaha keyboard with a bad voltage regulator. It has an On/Off switch Pin 4 on a 4 pin package. I replaced it and got nothing until I accidentally shorted Pin 4 to ground. Then it worked. So as a last ditch suggestion with No Guarantees, if there is a voltage regulator with an On/Off switch pin associated with those connectors, UNPLUG THE MACHINE and try shorting it or the companion capacitor to ground. MAKE SURE THE POWER IS OFF.

pinballdaveh 11-11-2015 11:52 AM

what a mistake on williams part to design a wire termination jack connector system that would allow this to happen. instead of using 2 connectors the same size why not use 4 connectors all with different amount of pins, different sizes, and keyed different. that should make connector assembly mistakes to a minimum. its hard to imagine what voltages going to parts of the boards that dont belong. sorry to say this but the cpu, power supply, and driver boards should be sent to a board tech or be replaced. sounds and speech boards might have been spared because they arent involved directly with the playfield.

ganastas 11-11-2015 02:50 PM

Thanks for the responses,

I'm going to try and repair it myself. I'm pretty good with an soldering iron. I'll replace those parts in the first reply and report back on my results. This will take a while as I can do all this at work in my down time.

Thanks again, and if any more ideas post um up.

Ike Savage 11-11-2015 03:42 PM

hopefully really good with a soldering iron in terms of working with IC's and other heat-sensitive components. also equipped with the right testing and diagnosis gear. so basically a board tech yourself?

ganastas 11-11-2015 07:09 PM

No, not a board tech. But I'm a Aircraft Maintenance Engineer Avionics actually. So I've done my fair share of soldering over the last 19 years. I just need the help on which components I need to replace after my HUGE mistake (feel like such a dummy). I just ordered all the items I require and I'm going to replace them with IC sockets as well (just in case it happens again). We have all the items at work to replace this properly, anti static work bench and all. Just hope its the correct ones that need replacing. As IC 7 was the one smoking hot.

sleepy 11-11-2015 08:16 PM

I seem to remember that the early SS machines went to hard soldered ICs because they had problems in the field with warm IC's popping out of their sockets.

Ike Savage 11-11-2015 11:02 PM


Originally Posted by sleepy (Post 106302)
I seem to remember that the early SS machines went to hard soldered ICs because they had problems in the field with warm IC's popping out of their sockets.

i remember that as being a big problem with apple ]['s for awhile. every couple days or so you had to pop the lid and gently press them all down. no vibration necessary!

but maybe since then (around 1980), sockets and IC's are better engineered. *shrug*

pinballdaveh 11-12-2015 09:58 AM

Early SS CPU and MPU boards used ic sockets made by scanbe. these sockets were garbage. poor pin connections were made at the sides of the ic pins instead of the flat front and back sides of the ic pins. over time the connections would loosen and cause problems. these ic sockets were mostly used for game program eproms but might have been used for PIA's and MPU chips also. with the board removed from the machine , if you grip the ends of the chip with your fingers and gently rock the chip back and forth and if the chip comes out easily ( being very careful not to damage the chip pins ) chances are its in a scanbe or a defective socket.

ganastas 11-22-2016 12:31 PM

Ok, I'm back. been a while. But I carried out the repair as above hooked it all up. Wish I had better news, however the gp lights come on and the board goes into diagnostic mode always showing ic 13 is bad. Better then what is used to do. Opened coin door and turned off and on twice no fix as the battery pack in not installed. What to you guys think? Should replace ic 13 and 16? Not sure if this board can carry out its full diagnostic will the ram failing. Or I'm I going to end up replacing every chip lol.. Thanks your help.


Coil_Smoke 11-23-2016 05:11 AM

Games act up in various ways when back-up batteries fail. Does connecting the battery have any effect?

Johanedre 04-27-2017 06:22 PM

I have an issue that is very similar to yours. Did you managed to fix that?

ganastas 05-14-2017 09:06 PM

Update. Ya, I know it's been long long time. Tried new battery's no fix.
Fault code still one on boot? We have to get this bro's could be a great fix post.
From bad deign..

ganastas 07-23-2018 12:42 PM


I changed out IC's 5, 7 and 12 on the cpu. Then IC 17 on the driver board. Now at least the digital display on the cpu goes from 0 to 1 and continues the same after pushing the bite test. As error 1 indicates bad ram. I changed them both out. Still no fix same issue. I've read that if IC 13 is bad you should change out IC 20 as well? isn't that the flipper ROM. how do i do that?


boydsc331 07-24-2018 11:09 PM

just replace the whole board and be done with it. Rottendog or something like that.

ganastas 08-02-2018 07:01 PM

Yup, did just that. Got a swemmer system 7 board with new roms. Put it in today. And its ALIVE, ALIVE. Still gotta get my original looked at for back up.

I'll never do this again!

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