One flipper does nothing while the rest of the game works.

Flipper dead: burned coil

Cause: A burned flipper coil, usually because the button was held while the end-of-stroke switch failed to open, or because broken linkage jammed the EOS switch.

Checks

• Raise the playfield and look at the coil wrapper; dark or charred paper suggests burning.
• Try to move the plunger by hand; a seized plunger points to a burned coil and melted sleeve.

Fix

• Replace the coil (and sleeve).
• Find the cause first: check the EOS switch gap and look for a broken bracket or link jamming it.

Systems

• Williams System 3
• Williams System 4
• Williams System 6 / 6A
• Williams System 7
• Williams System 9
• Williams System 11
• Williams System 11A
• Williams System 11B
• Williams System 11C
• WPC Alpha-Numeric
• WPC Dot Matrix
• WPC Fliptronics
• WPC DCS
• WPC-Security (WPC-S)
• WPC-95
• Bally MPU AS-2518-17
• Bally MPU AS-2518-35
• Stern MPU-100
• Stern MPU-200
• Bally 6803
• Gottlieb System 1
• Gottlieb System 80
• Gottlieb System 80A
• Gottlieb System 80B
• Gottlieb System 3
• Data East CPU Version 1/2
• Data East CPU Version 3
• Data East/Sega CPU Version 3b
• Capcom
• Electro-mechanical

Related tips

• Replacing a flipper coil
• Flipper dead: wiring or coil winding
• Flippers dead: fuse and coil voltage
• One flipper dead with fuses good
• Flipper coil numbers carry two windings
• Flippers dead during play: check the "U" relay
• Flipper dead on a System 11 game
• Flippers and lock kickout dead with good fuses

Source: Pinball Machine Care & Maintenance, Bernard B. Kamoroff (Bell Springs Pinball Alley)