820-3115, Question Re: Battery-Detect/SMBUS

[SMMRepair]

I got a unit in today with the issue reported as "doesn't see battery; "x" over battery; issue is on-and-off". Figured it was going to be the usual dying SMC, pretty typical. I got the board out and noticed that someone had "repaired" the primary speaker connector (next to the iSight connector) on the board. Their fix was simply to bridge all 4 pins and call it a day. It didn't cause any immediate issues for them I guess, however, I was wondering if this could in any way be related to the reported battery-detect issue? I ask, because I didn't test the board with the obviously-fucked speaker connector, and once I did test it, after properly replacing the speaker connector, I'm not noticing any battery-detect issues. Of course, dying SMCs can be inconsistent (work/not work before finally not-working at all), however I'm wondering if the speaker connector pins being bridged (and knowing the SMC is partially related to audio output) may have been the cause of (or at least related-to) the battery-detect issue, and NOT the SMC. Is this possible, or totally unreasonable? I've had SMCs fail in a way that audio didn't work, so I was wondering about this situation.

I'm going to monitor the unit for a few days to see if the battery issue pops up, and would normally replace the SMC "to be safe", but since the speaker connector issue is a part of the scenario now, I figured I'd ask in the meantime.

Thanks in advance!

 

[smiba]

Speaker connector repair has very unlikely anything to do with it. Its not even on the same bus.

Battery not being detected is usually Bad battery, crap underneath the SMC, Broken SMC and/or Broken ISL, Bad battery indicator, bad resistors (R5280/81). In about that order, but obviously it depends on the history of the device.

Since its a on/off issue and the issue only affects the battery readout, I'd say try a different battery. If you want you can check the resistors as well to be sure since that takes less then a minute.

 

[SMMRepair]

Thanks, smiba. Yeah, I'll check all the obvious/typical stuff once I let the unit run for a bit, hoping to catch the battery failure. If the speaker connector can have absolutely no bearing on the battery-detect of the SMC, then I'm sure the issue is the SMC (as usual). And yes, I agree, I wouldn't think the speaker connector can have any affect on the battery-detect functions of the SMC, but with all the weird shit I've seen on these boards at this point, I thought I'd ask.

 

[smiba]

If a new battery doesn't solve it try a reflow of the SMC first, use a nice amount of flux. If its the SMC thats at fault its likely in the solder.