Genesis:Repair High Failure Rate Tengen Games

Known issue
Several Tengen published games for the Sega Genesis have high failure rates. There is an apparent issue with the 800068-01 REV A PCB where at least some experience a loss of via conductivity with time. Not all of the games which use this PCB seem to have high failure rates, so it might be restricted to certain batches which would be identifiable by the date code printed in copper on the top side of the PCB.

Symptom
Games affected are often completely non-functional. The issue can be confirmed by measuring resistance between the contacts on the "B" side of the edge connector and the corresponding pins on the ROM chip. An unaffected board should measure below 2 ohms, while an affected board will give a resistance that can be as high as 100 ohms which varies pin to pin. In some cases the vias may be fully open circuit.

Note about name change
Tengen was renamed to Time Warner Interactive in the middle of these boards being produced and sold. This article will refer only to "Tengen", but TWI branded games may possibly also be affected.

List of potentially affected games
While the 800068-01 REV A PCB supports 16 megabit ROMs, Tengen also used it for smaller games. In some cases, these boards were even fit with 40-pin ROM chips, leaving the two holes on the pin 1 side empty. It appears that there was a period where Tengen switched to using this board for most of their titles including ones that had previously shipped with Sega-branded boards or the 40-pin 800057-02. Thus, games in this list may or may not use the affected PCB, depending on age. Additionally, later "cardboard box" releases of these games use Majesco-style cartridges with yet another PCB design.

Incomplete list of Tengen games confirmed to use this PCB:
 * Grind Stormer (US)
 * Dragon's Revenge (US)
 * Gauntlet IV (US)
 * RBI Baseball '94 (US)
 * Awesome Possum (US)
 * Hard Drivin' (US)
 * Kawasaki Superbike Challenge (US)
 * Lawnmower Man (US)
 * Red Zone (US)
 * Steel Talons (US)
 * Rampart (US)

Known affected PCB date codes
For the purposes of this table, a board is "good" if all vias measure less than 2 ohms, and "bad" otherwise.

Clean the vias
If the vias are cleaned the game will boot.

Pick one of the possible cleaning tools:
 * Leg of a component, such as a resistor or capacitor (I found this was the perfect tool as these are designed to be the perfect fit for the vias)
 * Needle
 * Dental Pick
 * Sim Tray tool


 * 1) Open the cartridge to gain access to the PCB.
 * 2) Flip the PCB to the rear side.
 * 3) Use the tool to make sure the all the holes are clear. I found with the component leg I simply had to push until the leg came out of the other side of the PCB.
 * 1) Clean PCB with compressed air and 91% or greater isopropyl.
 * 2) Reassemble cartridge and test.

This solution should keep your game working for a long while. Unfortunately due to the flawed nature of the design it will likely fail in the same way again. At that point you can simply clean the vias again.

Repair the vias
The via's can be repaired but will require the rom chip to be removed and replaced afterword. See this guide for how to repair vias.

Replacement PCBs not recommended last resort
HshYu2q46HU Todo: John Riggs claims that these PCBs are designed to work without capacitors? No evidence provided as to why this is safe? Anyone know anything about what these capacitors are for? Replacement PCBs https://www.vgcables.com/product/sega-genesis-replacement-pcb-rom-cartridge/

The rom chips can be swapped to a donor game's PCB. All 1GB games should be compatible.

List of compatible donor games (potentially incomplete) : TODO clean up this list
 * Addams Family, The
 * 05/26/2004 12:39 PM         1,048,576 Adventures of Mighty Max, The (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Aero the Acro-Bat (U) [b1].bin
 * 10/28/2000 11:00 PM         1,048,576 Aerobiz (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Aerobiz Supersonic (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Alisia Dragoon (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 American Gladiators (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Animaniacs (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Another World (E) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Arcus Odyssey (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Atomic Runner (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Ayrton Senna's Super Monaco GP II (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 B.O.B (UE) (REV01) [!].bin
 * 05/26/2004 12:00 PM         1,048,576 B.O.B (UE) (REV01) [h1C].bin
 * 10/28/2000 11:00 PM         1,048,576 Barkley Shut Up and Jam! (UE) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Batman - Revenge of the Joker (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Battletoads and Double Dragon (U) [c][!].bin
 * 10/28/2000 11:00 PM         1,048,576 Beast Wrestler (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Beauty and the Beast - Belle's Quest (U) [!].bin
 * 09/20/2003 01:06 PM         1,048,576 Beauty and the Beast - Roar of the Beast (U) [b1].bin
 * 10/28/2000 11:00 PM         1,048,576 Berenstain Bears', The - Camping Adventure (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Best of the Best - Championship Karate (U) [c][!].bin
 * 10/28/2000 11:00 PM         1,048,576 Bill Walsh College Football (UE) [c][!].bin
 * 10/28/2000 11:00 PM         1,048,576 Bio-Hazard Battle (UE) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Blades of Vengeance (UE) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Blaster Master 2 (U) [c][!].bin
 * 10/28/2000 11:00 PM         1,048,576 Bonkers (UE) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Boxing Legends of the Ring (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Bram Stoker's Dracula (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Bubba N Stix (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Buck Rogers - Countdown to Doomsday (UE) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Bulls vs Blazers and the NBA Playoffs (UE) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Bulls vs Lakers and the NBA Playoffs (UE) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Cal Ripken Jr. Baseball (U) [b1].bin
 * 05/26/2004 12:01 PM         1,048,576 Caliber Fifty (U) [!].bin
 * 05/26/2004 12:01 PM         1,048,576 Capt'n Havoc (E) [!].bin
 * 05/26/2004 12:01 PM         1,048,576 Captain America and the Avengers (U) [!].bin
 * 09/03/1996 11:48 PM         1,048,576 Castlevania - Bloodlines (U) [!].bin
 * 10/07/1996 06:06 PM         1,048,576 Chakan - The Forever Man (UE) [!].bin
 * 03/28/1994 02:33 PM         1,048,576 Chameleon Kid (J) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Champions World Class Soccer (W) (M4) [!].bin
 * 05/26/2004 12:01 PM         1,048,576 Championship Pool (U) [!].bin
 * 08/17/1997 03:56 AM         1,048,576 Chavez II (U) [!].bin
 * 05/26/2004 12:35 PM         1,048,576 Chester Cheetah (U) [c][!].bin
 * 09/02/1996 09:38 AM         1,048,576 Chester Cheetah 2 - Wild Wild Quest (U) [!].bin
 * 05/26/2004 12:35 PM         1,048,576 Chi Chi's Pro Challenge (U) [!].bin
 * 05/26/2004 12:35 PM         1,048,576 Chiki Chiki Boys (UE) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Chuck II - Son of Chuck (U) [!].bin
 * 03/31/1997 06:15 AM         1,048,576 Chuck Rock (U) [b1].bin
 * 10/28/2000 11:00 PM         1,048,576 Combat Cars (UE) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Cool Spot (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Crystal's Pony Tale (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Cyber-Cop (U) [c][!].bin
 * 10/28/2000 11:00 PM         1,048,576 D&D - Warriors of the Eternal Sun (UE) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Dashin' Desperadoes (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 David Crane's Amazing Tennis (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Davis Cup World Tour Tennis (UE) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Deadly Moves (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Death Duel (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Desert Demolition (UE) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Desert Strike - Return to the Gulf (UE) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Dinosaurs for Hire (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Double Dragon 3 - The Rosetta Stone (UE) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Dr. Robotnik's Mean Bean Machine (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Dragon's Revenge (UE) [!].bin
 * 08/29/1996 01:11 AM         1,048,576 Dune - The Battle for Arrakis (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Earnest Evans (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 ECCO Jr. (U) (REV00) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 ECCO The Dolphin (UE) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 El Viento (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Ex-Mutants (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Exile (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Exo-Squad (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 F-15 Strike Eagle II (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 F1 World Championship (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Ferrari Grand Prix Challenge (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Fun-N-Games (U) [b1].bin
 * 07/15/1997 08:32 PM         1,048,576 G-LOC Air Battle (W) [b1].bin
 * 10/30/1999 11:00 PM         1,048,576 Gadget Twins, The (U) [!].bin
 * 06/23/2001 11:00 PM         1,048,576 Gaiares (JU) [!].bin
 * 08/25/1999 11:00 PM         1,048,576 Galaxy Force II (W) (REV00).bin
 * 06/23/2001 11:00 PM         1,048,576 Gauntlet 4 (UE) (Aug 1993) [!].bin
 * 09/01/1996 11:00 PM         1,048,576 GemFire (U) [!].bin
 * 06/23/2001 11:00 PM         1,048,576 General Chaos (UE) [!].bin
 * 07/18/2001 11:00 PM         1,048,576 Generations Lost (UE) [!].bin
 * 08/06/2000 11:00 PM         1,048,576 Genghis Khan II - Clan of the Gray Wolf (U) [!].bin
 * 08/06/2000 11:00 PM         1,048,576 George Foreman's KO Boxing (U) [!].bin
 * 07/18/2001 11:00 PM         1,048,576 Gley Lancer (J) [!].bin
 * 08/25/1999 11:00 PM         1,048,576 Gods (U) [!].bin
 * 04/06/2012 05:01 PM         1,048,576 Golden Axe III (F) [!].bin
 * 05/19/1998 11:00 PM         1,048,576 Golden Axe III (J) [!].bin
 * 03/30/1997 11:00 PM         1,048,576 Goofy's Hysterical History Tour (U) [!].bin
 * 08/25/1999 11:00 PM         1,048,576 Great Waldo Search, The (U) [!].bin
 * 09/01/1996 11:00 PM         1,048,576 GRIND Stormer (U) [!].bin
 * 06/23/2001 11:00 PM         1,048,576 Gunstar Heroes (U) [!].bin
 * 05/26/2004 12:37 PM         1,048,576 HardBall! (U) [!].bin
 * 05/26/2004 12:37 PM         1,048,576 Heavy Nova (U) [!].bin
 * 08/13/2000 07:09 PM         1,048,576 High Seas Havoc (U) [!].bin
 * 05/26/2004 12:37 PM         1,048,576 Humans, The (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Immortal, The (UE) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Incredible Crash Dummies, The (UE) [c][!].bin
 * 10/28/2000 11:00 PM         1,048,576 Indiana Jones and the Last Crusade (U) [c][!].bin
 * 08/26/1997 11:03 PM         1,048,576 Jack Nicklaus' Power Challenge Golf (UE) [!].bin
 * 08/13/2000 07:57 PM         1,048,576 Jerry Glanville's Pigskin Footbrawl (U) [!].bin
 * 03/19/1999 05:47 AM         1,048,576 Joe & Mac Caveman Ninja (U) [!].bin
 * 05/26/2004 12:37 PM         1,048,576 Joe Montana Sports Talk Football 2 (W) (REV00) [!].bin
 * 08/23/2000 12:29 PM         1,048,576 John Madden Football '93 (UE) [c][!].bin
 * 10/31/1999 02:02 PM         1,048,576 John Madden Football '93 - Championship Edition (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Journey From Darkness - Strider Returns (U) [c][!].bin
 * 07/18/2001 11:00 PM         1,048,576 Kawasaki Superbike Challenge (UE) [!].bin
 * 06/23/2001 11:00 PM         1,048,576 Kid Chameleon (UE) [!].bin
 * 08/06/2000 11:00 PM         1,048,576 King of the Monsters (U) [!].bin
 * 07/18/2001 11:00 PM         1,048,576 Last Action Hero (U) [!].bin
 * 07/18/2001 11:00 PM         1,048,576 Lawnmower Man, The (UE) [!].bin
 * 07/18/2001 11:00 PM         1,048,576 Legend of Galahad, The (UE) [!].bin
 * 08/06/2000 11:00 PM         1,048,576 Lemmings (JU) (REV00) [!].bin
 * 08/06/2000 11:00 PM         1,048,576 LHX Attack Chopper (UE) [!].bin
 * 12/07/1998 11:00 PM         1,048,576 Lightening Force - Quest for the Darkstar (U) [c][!].bin
 * 08/25/1997 11:00 PM         1,048,576 Lost Vikings, The (U) [!].bin
 * 07/18/2001 11:00 PM         1,048,576 Lotus Turbo Challenge (UE) [!].bin
 * 05/26/2004 12:38 PM         1,048,576 Magic School Bus, The (U) [!].bin
 * 08/01/2000 07:12 PM         1,048,576 Marvel Land (U) [!].bin
 * 08/26/1999 07:26 PM         1,048,576 Mazin Saga (U) [!].bin
 * 06/02/2000 08:58 AM         1,048,576 McDonald's Treasure Land Adventure (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Mega Bomberman (UE) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Mega Turrican (U) [!].bin
 * 05/26/2004 12:38 PM         1,048,576 Menacer 6-in-1 Game Pack (UE) [!].bin
 * 05/26/2004 12:38 PM         1,048,576 Mercs (W) [!].bin
 * 05/26/2004 12:39 PM         1,048,576 Mick & Mack as the Global Gladiators (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Mickey's Ultimate Challenge (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Midnight Resistance (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Mig-29 Fighter Pilot (U) [!].bin
 * 05/26/2004 12:39 PM         1,048,576 Mike Ditka Power Football (U) [!].bin
 * 05/26/2004 12:39 PM         1,048,576 Minnesota Fats Pool Legend (U) [!].bin
 * 10/31/1999 08:43 PM         1,048,576 MLBPA Sports Talk Baseball (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Mr. Nutz (E) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Muhammad Ali Heavyweight Boxing (U) [b1].bin
 * 10/28/2000 11:00 PM         1,048,576 Mutant League Football (UE) [!].bin
 * 05/26/2004 12:39 PM         1,048,576 NBA All-Star Challenge (UE) [!].bin
 * 05/26/2004 12:39 PM         1,048,576 NCAA College Football (U) [!].bin
 * 10/31/1997 07:50 AM         1,048,576 NHL 94 (UE) [!].bin
 * 09/02/1999 08:45 AM         1,048,576 Nigel Mansell's World Championship (U) [!].bin
 * 09/02/1996 03:24 PM         1,048,576 Ninja Gaiden (Beta).bin
 * 05/26/2004 12:40 PM         1,048,576 Normy's Beach Babe-O-Rama (UE) [!].bin
 * 05/26/2004 12:40 PM         1,048,576 Ooze, The (JU) [!].bin
 * 08/26/1997 03:55 AM         1,048,576 Operation Europe - Path to Victory 1939-1945 (U) [!].bin
 * 08/14/2000 09:38 PM         1,048,576 Out of this World (U) [!].bin
 * 08/27/1999 12:15 AM         1,048,576 Outlander (U) [!].bin
 * 08/27/1999 03:36 AM         1,048,576 OutRun (W) [!].bin
 * 10/27/2000 01:16 AM         1,048,576 OutRun 2019 (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 P.T.O. Pacific Theater of Operations (U) [!].bin
 * 08/18/2000 11:50 PM         1,048,576 Paperboy II (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Pele! (UE) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Pete Sampras Tennis (UE) (REV00) (J-Cart) [c][!].bin
 * 10/28/2000 11:00 PM         1,048,576 PGA European Tour (UE) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 PGA Tour Golf II (UE) (REV00) [c][!].bin
 * 10/28/2000 11:00 PM         1,048,576 Pink Goes to Hollywood (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Pirates! Gold (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Pit Fighter (UE) (Jun 1991) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Power Monger (UE) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Predator 2 (UE) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Prince of Persia (U) [!].bin
 * 10/28/2000 11:00 PM         1,048,576 Pro Quarterback (U) [c][!].bin
 * 10/28/2000 11:00 PM         1,048,576 Puggsy (U) [!].bin