Hi friends
I’m shopping my #dw and none of the flashers are going in test mode.
I checked and replaced f111, which is the flasher secondary.
Haven’t dug in beyond that yet but would love some direction on where to focus next?
Thx gents.
Quoted from Bospins:I’m shopping my #dw and none of the flashers are going in test mode
I'm pretty sure you need to have the door closed to do this test or even the coil test.
Yeah...thanks for that...tried pushing the white door button in, no change. The door close button does trigger in the switch tests.
All the solenoids work no problem (flippers, pops, kickers).
Maybe the weird playfield glass switch needs to be closed also? I’ll try that too.
It’s weird that it’s just the flashers and only the flashers.
Quoted from Bospins:Maybe the weird playfield glass switch needs to be closed also? I’ll try that too.
Be careful with that. That switch disables the time expander up/down. That sucker can cut your fingers off if you're not careful.
Ok - no reading at 20v test point - tp7.
Since f111 is new, that leaves on the bridge rectifier br4 as the culprit.
I can’t get my probes in there to check the input and output of br4 so I’ll have to pull the board...
Before I start doing surgery, do you guys agree?
Quoted from Bospins:Is this an ok part?
Yes.
Or support Ed - https://www.greatplainselectronics.com/proddetail.asp?prod=GBPC3504W
LTG : )
Quoted from Bospins:I have to pull the board to replace a header anyway.
Thanks Lloyd and everyone else.
Re-flow the headers, possible cracked solder joints.
I doubt the bridge is bad. Even if one or more diodes would be open (rare), there would still be some voltage output, but lower than expected. Before replacing the bridge, which could easily do more damage than good, do a few voltage checks. It's an extremely simple circuit. Check AC volts coming into the board at J102, one probe on pin 1 or 2, other probe on pin 3 or 4. Expect 15-20vac give or take. If that is not there no need to fool with the board, probably the coin door interlock switch would be bad or wire disconnected. If AC volts are there follow the path to the AC pins on the bridge, and make sure AC is there. If ac there, make sure ground to the bridge is connected and see if 20v is coming out of the bridge. If so, but not at the test point, find the open on the board. These things usually crop up when guys replace the capacitors and or bridge and damage the board. For sure don't replace the bridge without doing some checks first.
Thanks. I’ll do some checks. Coin door interlock is working on the switch edge test so I think that’s ok.
Testing the board components with power applied will be tough. I don’t have a test harness and getting on the pins while the board is in the game is impossible.
I’ll do a few checks but I think pulling the board for a good look is probably the next step.
Once you pull the board the simplest thing to start with us continuity tracing of that circuit from the AC input pins to the fuse.
Quoted from Bospins:Coin door interlock is working on the switch edge test so I think that’s ok.
No, the memory protect switch is working in switch edge test.
High power interlock only has high power going through it. Nothing to let the game know if it's open or closed.
LTG : )
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