How to read the flashes on the last four 6803 games

Atlantis, Truck Stop, Blackwater 100 and Escape from the Lost World run all tests first and boot without flashing if nothing failed (a faint flicker is normal). If a test fails, the LED flashes once per test that passed, so three flashes points at the fourth test, the U4 RAM.

Systems

• Bally 6803

Games

• Atlantis
• Blackwater 100
• Escape from the Lost World
• Truck Stop

Related tips

• Nine-flash LED code meanings
• Expected CPU LED flashes by game
• Eight-flash LED code meanings
• Truck Stop and Atlantis: 6803 games built by Williams
• CPU LED stops just short of the full count
• CPU never starts: check the reset line at U1 pin 6
• Game boots but will not take credits or start
• Nonsense adjustment values after a battery failure

Source: Repairing Bally 6803 Pinball Games from 1985 to 1989, Clay Harrell (pinrepair.com)