The flipper kicks up but will not stay up while the button is held.

Flipper fires then falls straight back

Cause: Open hold (thin) winding, usually a broken wire at a coil lug, or a bad flipper board.

Checks

• Briefly ground the coil end lug (test point 3); the plunger should pull in gently.
• If it does, ground the hold output at J802 (test point 4); if that also holds, the flipper board is faulty.

Fix

• Resolder a broken fine-wire lead at the lug if possible, otherwise replace the coil.
• Repair or replace the flipper board if the coil holds when grounded.

Systems

• WPC Fliptronics
• WPC DCS
• WPC-Security (WPC-S)
• WPC-95

Related tips

• Fliptronic flipper dead: check the button first
• How Fliptronic flipper drive works
• Earlier WPC flipper controller board connectors
• Flipper energises at power-on (Fliptronic)
• Flipper fires and double-taps but won't stay up when held: bad flipper coil
• Fliptronics: flipper will not hold up (flutters)
• All flippers kick once at game start and then go dead
• Flipper fires twice quickly and won't stay up: broken hold winding wire on the coil

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