Match and special replays work, but reaching a replay score never adds a credit on any of the four players.

Replay scores never award a credit: cracked joints on the score reel boards

Cause: The small circuit boards on the score reels (the thousands reels for replay scores) had cracked solder joints in all directions on every reel.

Checks

• When the fault affects every player, check what they share first: the switch on the L relay (if the 1000-point chime works it is fine) and the player unit wiper and its disc wiring.
• Inspect every score reel's circuit board for cracked joints, including the tens reels used for match.

Fix

• Repair the cracked joints on each reel board; where they won't take fresh solder, move the wires to sound points.

EM games have 120 V AC in the cabinet wiring; unplug the game before working near the transformer and line wiring.

Systems

• Electro-mechanical

Games

• Bronco

Related tips

• Williams reset problems: cracked joints on score reel switches
• Players 3 and 4 reset but players 1 and 2 never do at game start
• 10,000 score reel resets but never scores in play: loose wiper fingers
• Every hundred-point score also adds a thousand
• Player 1 hundreds reel steps only sometimes: dirty contact on the player 2 relay
• 1,000-point reels reset but never score for any player: failed 1,000-point relay coil
• Score reels by maker
• How score reels come out, by maker

Source: Pinball Repair help group!! (Facebook group)