Every CPU-controlled coil is dead.

None of the CPU-controlled coils fire

Cause: The +24 V DC rectifier fuse or rectifier, a broken 24 V feed to the coils, or the driver or control board.

Checks

• Check the fuse for the +24 V DC rectifier on the bottom board.
• Measure the +24 V DC rectifier output.
• Measure +24 V DC at any controlled coil; if it is missing there, check the cabling to the driver board and playfield.

Fix

• Restore the 24 V supply; if it is present, replace the driver board, then the control board.

Systems

• Gottlieb System 80
• Gottlieb System 80A

Related tips

• Coil command lines during test step 17
• None of the controlled playfield lamps work
• Game Over (Q) and Tilt (T) relays are not fused
• One or more controlled lamps never light or stay on
• A driver board output is stuck on or dead
• Driver board A3-J4 coil outputs
• How driver board coil transistors are switched
• Where coil, sound and lamp commands come from

Source: System 80 Service Manual, Gottlieb