(Topic ID: 218436)

So uh... what happens when switch matrix shorts to lamp matrix....?


By trueno92

1 year ago



Topic Stats

  • 11 posts
  • 5 Pinsiders participating
  • Latest reply 1 year ago by zacaj
  • Topic is favorited by 1 Pinsider

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#1 1 year ago

This is an extension of the post I have in the tech Modern sub-forum... looks like no one in there has been stupid enough to pull this off, but wait, i am.

I shorted the lamp matrix column that handles the cabinet buttons against the switch matrix for the claw handle buttons...

It was really late and i was reassembling the left handle and i kept seeing the switch matrix line light up when i tightened the handle screws all the way. if i left them a little tight, it was fine.. anyway I cranked down on it and the wires pressed through the insulation and shorted against each other - i am using led lit claw thumb buttons - next time i know to take 3 seconds and move the wires away properly...

as a result fuse f114 blew (8a) and now i have some lights in my light matrix that seem to be lighting even tho they are on separate columns in the matrix. So if ball save lights, so does the center ramp light...

ok... uh.. help?

#2 1 year ago

It's the other thing you have to worry about. U20 on the switch matrix often dies when this happens. Check all your switches.

#3 1 year ago

switches seem to be ok, they are still registering ok on the switch tests.. I will go over them again, but thanks for this.

for lamps, i have disconnected J137 and did a continuity test between pin 1 and pin 9 that correspond to the columns that seem to be lighting at the same time when i go through the bulb test... and there is no continuity between them,.

#4 1 year ago

Step one, did you fix the wires?

#5 1 year ago

I'd guess one of your lamp transistors is stuck on

#6 1 year ago

I had a South Park that had a row of lamps stuck on bright and would ghost other lamps. It was a shorted driver transistor. Different manufacturer but similar operation.

#7 1 year ago
Quoted from CadillacMusic:

Step one, did you fix the wires?

I separated them from each other.

The look of disbelieve of seeing threads I just pressed into and thru the insulation must have been priceless...

#8 1 year ago
Quoted from zacaj:

I'd guess one of your lamp transistors is stuck on

I'm hoping ur right.... now to find out which one...

So effectively the lamps on thie column are basically being driven by its correct transistor and the other one that's not turning off? But at the same time?

#9 1 year ago

Wrap 'em in electrical tape for safety's sake. Then look at your lamp matrix, as see what precisely is out. Use the lamp test to go through one by one.

#10 1 year ago

Check your entire switch matrix for ghost activations, it is possible you damaged the U20 integrated circuit on the MPU.
Next you have to test your entire lamp matrix and note deviations or incorrect lighting so you can further troubleshoot.
This is making the assumption you already reseparated the gun handles on DM so you do not have the continuing short.

Shrink wrap tube please, no electrical tape.
Buy multiple sizes, it is not that expensive.
Do repairs correctly.

#11 1 year ago
Quoted from trueno92:

I'm hoping ur right.... now to find out which one...
So effectively the lamps on thie column are basically being driven by its correct transistor and the other one that's not turning off? But at the same time?

No, the 'correct' transistor for that column probably isn't turning off all the way. Either it or its predriver is probably bad. Take out the driver and test them all with your DMM, I'll be the transistor for that column reads bad

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