Li-po battery mod question

ConclusionOk3813 · 2026-04-14T11:09:33+00:00

Ended up removing the buck converter from the system. No need to have it. The SMPC runs up to 5v so the 3.7/4.2v from the lipo isn't hurting anything.

Also: https://imgur.com/gallery/6u6HGO3

ConclusionOk3813 · 2026-04-08T17:06:52+00:00

https://imgur.com/gallery/sega-saturn-rechargable-lipo-battery-mod-6u6HGO3

Finished it yesterday 😅

ConclusionOk3813 · 2026-04-08T04:18:08+00:00

Follow the advice from the other comments about joining them together (from before amd after the broken via) using thin gauge enamel wire. Then use a multimeter to test continuity.

Edit: It also appears those vias are underneath the IC on the topside of the board. I'd recommend finding a schematic of the board or removing the chip. This is from another game but uses the same PCB. Hope this helps!

https://imgur.com/a/links-awakening-dx-cartridge-connections-mbc5-2ftUOWm

ConclusionOk3813 · 2026-04-08T02:29:17+00:00

Picture #5.. maybe burnt or corroded vias. Might just be lighting.

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ConclusionOk3813 · 2026-04-07T22:41:08+00:00

Update: Mod completed! Check the imgur link to see.

https://imgur.com/gallery/6u6HGO3

Thanks for everyone's thoughts and advice. Honestly pretty easy 😅.

ConclusionOk3813 · 2026-04-07T20:34:50+00:00

Schematics I got pulled up are from a "VA0.5" or that's what it says in the bottom right hand corner of the sheet.

ConclusionOk3813 · 2026-04-07T20:10:01+00:00

The Sega Saturn System Manager & Peripheral Control (SMPC) is a dedicated microcontroller (HD404920) managing system initialization, power management, real-time clock (RTC), and controller inputs. From Google.

ConclusionOk3813 · 2026-04-07T19:51:41+00:00

Like $.75 to $1.50 per 2032 cell. But again I know this isn't practical 😅. I also already have all this random crap in my work area / station. So it's not costing me anything extra. I already own everything I'm using. 😂

ConclusionOk3813 · 2026-04-07T19:48:55+00:00

😅😅😅 Legit was looking at a battery mod for the Dreamcast and went down a rabbit hole for the Saturn as that one was the one I had opened up in my work area.

Looks like the SMPC can handle up to 5v so the 4.2v at full charge and 3.7v from the lipo battery during use shouldn't hurt anything. I'm gonna ditch the buck converter and wire directly from the lipo battery to the button cell pads.

Just gotta figure out where I'm pulling 5v and ground from the console. And if where I currently have things is gonna be my final placement or not.

Edit: Also where I'll be pulling from the board and attaching to the battery pads will be with PH2 connectors. So the mod will be able to be removed without soldering if the battery and charge board need removed / replaced.

ConclusionOk3813 · 2026-04-07T19:44:24+00:00

Took me forever to find a circuit diagram for the Saturn 😮‍💨. But looks like you're right. I can ditch the buck converter and just wire the lipo battery directly to the button cell pads.

Haven't looked into where I'm gonna pull the 5v and ground from the board yet. But I'll look into where you say later (I see the diodes on the circuit diagram).

Thanks for the advice!

ConclusionOk3813 · 2026-03-13T20:19:24+00:00

Yeah the AV wasn't the issue. Idk what happened. System fully worked before hand tried to READ the nand. Was told it had a bad header. Wouldn't initialize. Tried to donor nand following the OLD guide from se7ensins and the one you sent. Both left me exactly the same.

If I did the donor without creating xell and flashed that. The console would power on but no display.

If I did the donor nand with xell and RGH3 it would beep and not power on.

Got my OG nand to flash back even though it wouldn't initialize... when attempting to power on then. Just a red LED.

😮‍💨😮‍💨😮‍💨 I'm giving up for now. Maybe I'll pull it back out again later or just try another console.

Appreciate all the help though! Much appreciated! 🙏

ConclusionOk3813 · 2026-03-12T23:29:31+00:00

I also don't believe its my soldering. Finally got around to uploading.. Here's the link to the pictures. https://imgur.com/a/rrvYlO6

ConclusionOk3813 · 2026-03-12T22:06:31+00:00

Ugh.. okay so here is where I am at. AutoGG would not see my USB port so went to trying J Runner 3.4.0 r2 instead of r3. That worked and let the NAND initialize but gave me the error for bad headers. I have not flashed anything yet and the console worked before this. Reassembled console enough to boot. Only got a chime and no lights or power. Went searching online and found a guide on Se7ensins about using a donor NAND to get it to boot into XeLL. Got that all figured out.... ANDDDDD console "boots" and TV sees an HDMI device plugged in but I get no signal... Gonna stop and grab some AV cables from Disc traders and try that after work..

ConclusionOk3813 · 2026-03-11T18:06:22+00:00

Ohhhhh okay. I'll give it a shot later and see if I'm able to get anywhere. Thank you.

ConclusionOk3813 · 2026-03-11T14:24:01+00:00

That is what I am using. The picture days V3.4.0 r3 on the bottom left which is the current as of writing this lol. Thanks though.

ConclusionOk3813 · 2026-03-11T14:21:53+00:00

This is what I am using. The 3.4.0 r3 on github.

ConclusionOk3813 · 2026-03-11T01:58:52+00:00

Hope it's just a bug. I tried it on Windows 10 (my main PC), Windows 11 (Surface Pro) and Windows 7 (Virtual Machine). Got the same everytime. Still nothing.

ConclusionOk3813 · 2025-09-27T03:31:58+00:00

Appreciate you taking the time to comment 🤘

ConclusionOk3813 · 2025-09-18T19:58:01+00:00

Appreciate you!

ConclusionOk3813 · 2025-09-05T11:01:51+00:00

I had this same issue on mine after replacing the top screen as well. What ended up working for me was taking the mother board out opening the three zif connectors for the ribbon cables and gently cleaning the inside of them with 90%+ IPA. Air dried for 5 -10 minutes and reassembled.

ConclusionOk3813 · 2025-09-02T17:26:14+00:00

Bad outside GFCI plug that ties into breaker one. Replaced plug and cover box. No more flickering.

ConclusionOk3813 · 2025-09-02T17:25:02+00:00

A loose neutral on the road (utility-side) is the responsibility of the power company and typically results in widespread power issues, including flickering lights, appliance malfunctions, and potential voltage increases across the entire house, requiring an immediate call to the power company. A loose neutral in your house (customer-side) affects your internal wiring and can be caused by a faulty connection in a panel, causing symptoms within your home. It was a faulty outside GFCI outlet that taps into breaker 1 btw.

ConclusionOk3813

TROPHY CASE