Scope.
This document is a repair guide for Williams System 3, System 4, System 6 and System 7 pinball games made from 1977 (Hot Tip) to 1984 (Star Light), and includes the famous Black Knight, Firepower, Gorgar and Flash pinball games. Updates of this document are available for no cost at http://marvin3m.com/fix.htm if you have Internet access. This document is three parts (part one is here, part two is here, and part three is here).

IMPORTANT: Before you Start!
IF YOU HAVE NO EXPERIENCE IN CIRCUIT BOARD REPAIR, YOU SHOULD NOT TRY AND FIX YOUR OWN PINBALL GAME! Before you start any pinball circuit board repair, review the document here, which goes over the basics of circuit board repair. Since these pinball repair documents have been available, repair facilities are reporting a dramatic increase in the number of ruined ("hacked") circuit boards sent in for repair. Most repair facilities will NOT repair your circuit board after it has been unsuccessfully repaired ("hacked").

If you aren't up to repairing pinball circuit boards yourself or need pinball parts or just want to buy a restored game, I recommend seeing the suggested parts & repair sources web page.

Table of Contents

1. Getting Started:
1. Experience, Schematics
2. Necessary Tools
3. Parts to have On-Hand
4. Game List
5. Different System Generations Explained

2. Before Turning the Game On:

1. Game Assembly & the Black/White Connectors!
2. Check the Coil Resistance.
3. The Power Supply (Explaination, Testing, Fuses, Bridges, Test Points, Modifications, Repair)
4. Batteries, the Battery Holder, Battery Corrosion, and the 5101 RAM
5. 40 Pin Interboard Connector (Dead Game or Random Lockups & Resets)
6. Power Connectors (Dead Game or Random Lockups & Resets)
7. Circuit Board Sockets (Dead Game or Random Lockups & Resets)
8. CPU Board Upgrades (System 3/4 to System 4/6 ROM Upgrades, etc.)
9. CPU/Sound Board Jumpers, ROM software, Flipper ROMs, DIP Settings.
10. Driver Board Checks & Upgrades (Burnt Resistors, etc.)
11. Testing Driver Board Transistors
12. General Illumination Connectors (Burnt GI)

3. When Things Don't Work:

1. Power-On Audit Mode, Funky Score Display Numbers (Battery/5101 RAM Problems)
2. Fixing a Dead CPU/Driver Board (CPU LED codes, Test EPROM, Blanking)
3. Diagnostics (Display test, Lamp test, Solenoid test, Switch test)
4. Random Lockups & Resets: What Causes Them & Testing For Them
5. Non-Working or Locked-on Coils/Flashlamps
6. Lamp Problems (the Lamp Matrix)
7. Switch Problems (the Switch Matrix)
8. Score Display Problems
9. Sound Problems
10. Flipper/Drop Targets Problems & Upgrades
11. Miscellaneous Oddities

Bibliography and Credit Where Credit is Due.
Lots of people contributed to this document, and I just want to say, "thanks!" Below are a list of the resources used in the development of this guide. Some resources/people may have been innocently left out, and many of the ideas in this repair guide are not original. If this is the case, and an idea is here that was originally yours, please notify me and I will make sure to give you credit!

• Mark Orthner (mark at techvantage.net), and his web page at pinball.flippers.info/system6resources.asp. Many ideas, pictures, advice came from Mark's site (with permission). Mark was instrumental in making this document happen, and contributed a great deal to the cause. If it wasn't for Mark, I would have never written this guide. Thanks Mark!! (or "damn you Mark!")
• Jerry Clause. Jerry is probably pretty sick of me asking him a zillion questions. He was indispensible in writing this guide.
• David Wagler, Des Moines IA (Dwagler at aol.com). David provided lots of broken boards and parts that were used in the development of this guide. I could not have done this guide without Dave's donated broken boards, wiring harness and displays!
• James Koempel, Keasnburg NJ, (j.koempel at verizon.net). James provided circuit boards used in the development of this guide. Again, it would have difficult to do this guide without his help.
• Jeremy Wilson. JW also provided a "box of boards" used in the development of this guide. Once again, it would have been difficult to do this guide without his help.
• Leon Borré and his system3 to system7 test EPROM at www.flipper-pinball-fan.be. Leon's test EPROM was great for diagnosing broken CPU/driver boards.
• Duncan "Scanbe" Brown. Duncan provided lots of tips and tricks. Did I mention Duncan *hates* Scanbe sockets?
• Frank-Rainer Grahl" (frgrahl at gmx.net).
• Mr. Johnson and his web site at www.aros.net/~rayj/action/tech. Ray's postings and tips were most helpful.
• Tuukka Kalliokoski's web page at "www.flipperit.net/tkalliok/flipperi/wms_en.html." Tuukka's web page was also very helpful in making this guide happen.
• Rob Hayes, who's advice and (lack of!) proof reading were very appreciated.
• David Gersic, who also did proof reading and provided some tips.
• John Robertson and his posts & tips helped mucho grande.
• "Solid State Flipper Maintenance Manual, Gorgor and later" (Tri-zone, Time Warp, Laserball, Gorgor), Williams Electronics #16P-496-100, December 1979.
• "Solid State Flipper Maintenance Manual, Firepower & Later Games", Williams Electronics #16P-497-100, March 1980.
• Pinball Liz Tech Reprints #1 to #6, August 1995 to August 1996, for their tips and tricks.