I posted this in the Transport The Rescue fanclub but I thought it would get better visibility here. I am trying to get two flashers working. I have confirmed via wire colour-coding that the two flashers circle below are "JET FLSHS C SIDE 05 04"
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The wire colour-code to both of these is black-yellow. These two flashers are part of the "special" solenoids.
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I've dealt with a similar problem in the past and it was the TIP122 at fault but I decided to go through the motions anyway to help train my brain with problems like this. I put the game in diagnostics mode, coil test, and then to the JET FLSHS. I put my logic probe on pin 6 of U20. The signal was pulsing so I followed the signal path to Q20, and then to Q24 and finally to 1J11-5. It pulsed the entire way, so my initial hunch of it being Q24 didn't pan out.
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On 1J11-5 the wire colour-code changes to gry-yellow. I followed this around to the Aux. Power Driver Board. Using my DMM I checked for continuity from 1J11-5 to the far end. All good.
So I moved to under the playfield. I'm measured 38VDC on each flasher (they are in series). So I followed the black-yellow back to the Interconnect Board in the backbox and check it for continuity. All good.
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So it's not the bulbs. I checked. I even swapped both with known good bulbs.
So it's not U20.
So it's not Q20.
So it's not Q24 (the TIP122).
It's not a break in the wiring from the CPU Board to the Aux. Driver Board.
It's not a break in the wiring from the flasher to the Interconnect Board.
The flashers are getting power.
This leaves me at something possible wrong on the Interconnect Board. Unless I skipped something? Any help would be appreciated.
Thank you,
Tim