PSB Subseries 8 Subwoofer Repair Troubleshooting & Advice

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Hi all! New here and to audio equipment. I'm trying to fix a Subseries 8 Subwoofer. It currently does not power on, which I believe is due to an incomplete circuit. I have reached out to PSB with similar questions, and am hoping they send me a service manual. For now, I wanted to share this with you all, in case there are very noticeable issues.

I have taken the following steps so far:

• Reconnected the pin-board for the volume, crossover, and power light
• Examined the circuit board for melted or damaged fuses
• Tried multiple power cords.

What I observed:
- The wire feeding into the actual speakers are only connected to the High Level L/R inputs.
- When these High Level L/R inputs are wired to a L/R output on my receiver, the subwoofer produces sound as expected.
- There are a few orphaned male connectors on the circuit that I believe may be meant to feed powered input into the speakers, namely U102, U103.

What I'm wondering:

• Are there any obvious connections that are missing?
• If so, do you guys have any recommendations for parts or steps to get it fixed up?
• Is there anything that stands out that would make this Subwoofer unsalvageable?
• Should there be a fuse where there's a huge amount of glue behind the power input?

In summary, there are currently only passive inputs wired into the subwoofer. My guess was the previous owner used a sub amp, but I'd like to get this restored to taking powered input. The subwoofer does work from passive inputs. The powered input literally never makes it to the actual speaker. I appreciate any and all input!

I have attached labeled pictures of the circuit.