On a solenoid expander game the ball is not kicked from the trough and a drop target falls instead when a game starts.

Expander games: check the controlled-lamp power first

Cause: The expander relay runs from the 6 V controlled-lamp bus, so a blown lamp fuse, the 20 A rectifier board fuse, an overheated lamp bridge, or blown under-playfield lamp fuses stop it; then the dead bulb beside the SEB, the MOC3011, the relay or the lamp driver SCR.

Checks

• If any controlled lamps are out, suspect missing lamp power to the expander.
• Check the 20 A fuse on the rectifier board, about 6 V AC into the lamp bridge and 6 V DC out.
• On later production runs check the bank of three fuses under the front right of the playfield.

Fix

• Replace blown fuses and a tired or self-desoldered lamp bridge with a heavy-duty one, then work through the SEB parts.

Systems

• Bally MPU AS-2518-35

Related tips

• Drop target falls instead of the ball being kicked out (SEB games)
• Centaur uses its solenoid expander for the ball-to-playfield kicker
• Expander game ejects or drops targets at the wrong time
• Drop target coils misfire after LEDs or a new lamp driver: expander boards need bulbs
• Solenoid expander relay buzzes or does not switch
• Expander-driven coils fire in pairs: drop target coil fitted without its second diode
• How the solenoid expander board doubles up coils
• Test the coils behind the solenoid expander

Source: Repairing Bally Electronic Pinball Games from 1977 to 1985, Part Three, Clay Harrell (pinrepair.com)