A special solenoid energises as soon as the game is turned on.

Sling or bumper locks on at power-up (System 11)

Cause: Shorted special solenoid driver transistor.

Fix

• Switch off and replace the TIP122 for that output.

Switch off fast to save the coil.

Systems

• Williams System 11
• Williams System 11A
• Williams System 11B
• Williams System 11C

Related tips

• System 11 coil outputs
• System 11 CPU/driver board transistor locations
• How System 11 special solenoids work
• F5 blows on a flip, then slings dead: shorted drivers and a loose coil power wire
• Kicker coil locks on again after a new TIP122: dead 7408 gate on the driver board
• The solenoid L/R select relay and transistor Q29
• Solenoid driver transistor positions on the CPU and PPB boards
• 50 V coils use PPB TIP36c transistors, pre-driven from the CPU board

Source: Pinball Machines: How They Work & Troubleshooting, Norbert Snicer