Fire a coil by grounding its driver tab

Steps

• Turn the game on.
• Find the solenoid driver transistors along the top edge of the CPU board.
• Touch a clip lead from ground to the metal tab of one driver for a moment only.
• The coil it drives should fire; if not, suspect the coil or its wiring rather than the driver.

Ground the tab only for a moment.

Systems

• Bally 6803

Related tips

• Expected LED-strip results on coil headers J6-J9
• How 6803 flash lamps are multiplexed
• Burnt coil connector after a locked-on driver
• The 19 solenoid driver transistors
• Solenoid driver transistor types
• Lamp driver SCRs on the CPU board
• Make an LED tester for lamp and coil outputs
• How 6803 feature lamps share SCR drivers

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