If the displays are strobing the slam switch mod must not be functioning correctly. I would go back and look at the mpu and try this slam switch mod. I bet he pin will boot then. As far as he flippers not working on one side check the tilt relay and the Q relay.\

Straight from pinwiki
6.1 Game Displays 000000 On Power Up and It's Not The Slam Switch

If you power the game on and all of the displays immediately display all zeros without strobing the problem is usually with the slam switch. However, if the slam switch modification has been done or the slam switch is working properly there is a problem with the switch matrix.

I had this problem on my Haunted House machine. I finally found that chip Z15 (7432) was bad.

I was fixing a kicker solenoid on the playfield, the playfield was still in the machine and fully in the upright position. While I was soldering the wire to the new solenoid I did not adequately protect the components below from a solder drip. Well, I did have a solder drip that landed right on a pop bumper driver board connector and shorted the connector. The short caused more than just this problem but for this narrative we will restrict to the slam/switch matrix problem.

Reading in other materials I recognized the problem as the slam switch issue. I used a logic probe to test other components and found the CPU board working, mostly as it should except for acting like the machine was slam tilted. There was little written about the problem outside of the slam switch. I decided to check the matrix by doing a diode check on all of the diodes in the switch matrix. When I did this, I found that many of the diodes were testing bad. These were being tested with the board removed from the machine.

Having replacement diodes in my parts drawer I decided that these must have gone bad during the short. I began unsoldering a few of the diodes. Once disconnected from the circuit board I remeasured the removed diodes and found the correct values on my meter, they were not bad. I then noticed that the bad diodes were all in the same row on the switch matrix. They all traced back to the Z15 chip. I replaced the Z15 7432 and the problem was resolved.

http://www.pinwiki.com/wiki/index.php?title=Gottlieb_System_80

slam mod

Slammod.png

Yeah i did the same on my Black Hole with the original mpu. It didnt work to well. Try the other one.

Awesome. I know a little bit about the system80's having owning a black hole and the knowledge of wealth on here,thanks to PinMike and all the others. They really are nice games when you do the correct mods and can give years of trouble free gameplay. This is actually a great place to be and to interact with other pinners. Not lke some of the other sites that when you ask a question after joining no one helps you because you just joined. So thanks again and welcome to the forms!