(Topic ID: 201392)

Roadshow - lamp matrix help needed

By jimy_speedt

2 years ago

Topic Stats

  • 4 posts
  • 2 Pinsiders participating
  • Latest reply 2 years ago by jimy_speedt
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Linked Games

#1 2 years ago


When I switch on the game, some ordered lamps are dark in game over mode, where they should blink as the other ones. These lamps correspond to the row 8 of the lamp marix. I tested Q83 which grounds the lamps of the row but this one looks good.

In addition, the start button lamp is on row 8, this one works. The wiring is connected to j135 pin 9. I presume that the driver works ok, and there must be something wrong with the row wiring in the cabinet. Voltage measured on both ends of the lamps is close to zero, stable.

I removed the row connector j133 and tested the voltages on each individual wire of the female plug. I read about 15vdc on each, except the row 8 which shows about 8 vdc.

At this point I have question, if connector j133 is unplugged, these voltages do not come from the driver board, where do they come from ? Then, what can explain that the row 8 wire (nb 9) reads a value lower than the others ?

Thanks for your valuable help

#2 2 years ago

I think you are reading power back through the matrix to the column wire.

#3 2 years ago

Maybe. Now what I find strange is that only one lamp of row 8 is good, but the wiring is specific to it. This one connected to j135 pin 9 is grounded properly by Q83. The others connected to j133 pin 9 aren’t. That’s beyond my understanding

#4 2 years ago

Solved. Wire broken under pf. Thanks

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