The power transistor (2N6059) on the auxiliary power supply that feeds the sound board fails again each time it is replaced, and the sound board is dead.

Sound aux supply keeps blowing its 2N6059: shorted capacitor on the 30 V rail

Cause: A dead short on the sound board's 30 V amplifier rail was overloading the supply. The short was a failed capacitor at C38 on the sound board.

Checks

• With power off, measure resistance from the sound board's 30 V rail to ground; a near-zero reading means a short on the board, not a supply fault.
• Pull the socketed chips and lift components on that rail one at a time until the short clears. Gottlieb traces are fragile, so check continuity after each lift.
• Tantalum capacitors usually fail shorted, so check those first.

Fix

• Replace the shorted capacitor (C38 here), then fit a new 2N6059 in the aux supply.
• While the board is out, consider replacing the electrolytic capacitors and repinning the backbox connectors.

Systems

• Gottlieb System 80

Games

• Haunted House

Related tips

• Replace C33 on the speech and sound board
• Haunted House and Black Hole sound board DIP switches
• No or low +5 V from the power supply
• No +5 V on a System 7 power supply
• Resets continue after diode repair: power and connector checks
• Lockups and odd behaviour from a heat-dried C1
• Sound supply fuse F8 blows after the game runs a while
• No sound and a burning smell from the sound board: diodes, then the board

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