Trough opto 3 won't trigger in switch test and an extra ball gets launched during multiball, even after reflowing the opto board, replacing the LEDs and receivers and fitting a new opto board.
Trough ball 3 opto never registers and extra balls launch: broken switch wire upstream
Cause: The switch matrix wire for that opto (white/orange) daisy-chains from the opto board to other playfield switches, including the extra ball switch and a VUK switch, before reaching the backbox. It had broken at one of those switches.
Checks
- Note which other switches share the dead opto's row or column; if one of them is also dead, the wire break is likely between them.
- Tug gently on the matrix wire at each switch along the chain.
- Use a jumper on the CPU switch connector in switch edges test to separate board faults from playfield wiring.
Fix
- Repair or replace the broken wire at the switch where it came loose.
Systems
Games
Related tips
- Most of switch row 6 dead, last switch works: broken row wire
- Several switches in one row never register: broken row wire at another switch
- Spinner stops registering: broken wire on an upper flipper EOS switch
- Several switches in one row or column dead: a broken daisy-chain wire
- One switch does not work
- Two or more unrelated switches trigger together
- One switch also triggers others in its column: bent diode on the mini playfield
- Switch matrix wire colors (all WPC games)
Source: Pinball Repair help group!! (Facebook group)