Helping a friend figure out how to correct a mistake he made. While replacing the upper right flipper coil (sleeve was stuck from previously getting too hot) he suspects he may have wired the new coil backwards..

When I get there I notice he has no DC voltage at the flipper coils, rather, I was getting AC voltage. Checked all the fuses on the Aux driver board and they all test good with continuity.

First thought was that the bridge rectifier was bad. Swapped it out today with another. But upon reinstalling in a Taxi I have in the house, it shows I have 50vac and 25vac coming in from connector J8 respectively but still no 50v DC coming out of J12 as it should be.

What are your thoughts on this? Theres not much to the circuit, so I feel like its something obvious I am missing.

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Using cabinet ground strap for ground.

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No change after replacing F7. Thinking about trying another bridge rectifier even though the 4 diodes inside this one test good both ways.

Let me know if you need another photo.

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I will check on this when I get home tonight. But wanted to add. The original bridge (4 diodes) tested fine in circuit. I was getting .4-.5 on all 4 diodes.

But when checking opposite direction looking for zero ohms, I was getting readings in circuit, only for a breif second.

Both the new and old bridge have this behavior and they both give good readings both ways out of circuit.

BR1 doesnt give faint readings at all when measuring 0 ohms. Maybe this is a moot point. But wanted to mention it.

Hit the nail on the head Grumpy. I could see the trace was fine, but never even occurred to check the solder joint on the topside. Had no continuity between the red arrow and fuse.

Flowed solder on topside. Difficult to reach with my iron. Not sure why solder wasnt wanting to flow through from the other side. But alas, i have continuity now where I didnt before. Going to toss it in taxi and test the outgoing DC now.

Thanks for the help,
Flash

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Great idea. I was afraid of burning up the trace/solder pad. So I was probably just being too careful. I will remember this tip for the next time.