Mid 2009 MacBook Pro 5,3 shuts down when unplugged. Probably not battery-related.

[Karma Cheetah]

First of all, a big thanks to all the Apple-enlightened of the forum that have helped myself and others with their expertise.

With that said, the reason I just made this account is because I have what appears to be a unique problem, as I haven't been able to find anything about it by searching the forum's older posts, nor elsewhere.

Short version: My Macbook Pro with two slightly dented charging pins has a ~50% chance of shutting down immediately when unplugged, but not when the connected charger is unplugged from the wall or unpaired from the power brick. Others have had similar problems, but it sounds like more of a battery issue than what I'm guessing in my case could be a charging port issue. Help?

Long version: The topic title sums up the problem, but more specifically, my MBP only shuts down when the charger is unplugged a certain way. Even then, it seems random. When the charger is jerked out very quickly (which is rare, but accidents happen) there seems to be a 50/50 chance of the laptop shutting down immediately. As in, black screen, fans shut off, etc. the instant it's unplugged. Dead laptop.

This only happens when unplugging from the laptop itself, never when disconnecting the charger brick or unplugging from the wall. When it does happen, I can only get the laptop to turn back on with the charger plugged in.

I've generally been able to avoid it by slowly and carefully pulling the charger upwards (kind of pivoting on its top edge) when I need to unplug. I have the older, boxy charger, not the new cylindrical one, if that makes a difference. I should also say that the charger light and battery lights behave normally.

I'm guessing it has little to do with the battery since unlike others' similar battery-related problems, I don't have an X over the icon and the behavior seems random, regardless of charge level. My battery is probably well beyond needing replacement, though (959 cycles and 63% design charge capacity), so it could certainly be to blame.

It's worth mentioning that my very mature and responsible friends were involved in an incident that involved my MBP falling a couple of feet and receiving two bent pins inside the charging port…thing. It's not very severe, but it's the leading culprit as far as I can tell so far. I'll post pics if needed.

Hopefully that covers everything. If specs are necessary, I'm happy to oblige. So, does anyone have any ideas what the real problem might be, or any ideas as to how to start diagnosing?

 

[GGJstudios]

Try resetting the SMC and calibrating your battery. Also see the link on troubleshooting MagSafe adapters in the CHARGING section of the following link.

This should answer most, if not all, of your battery questions:

Apple Notebook Battery FAQ​

 

[Karma Cheetah]

Thanks for the quick reply. I tried everything you mentioned; reset the SMC and by chance it turns out my regular habits already calibrate the battery fairly regularly. Would calibrating after a SMC reset be of any more benefit than if it were calibrated prior to the reset? If not, it seems I'm still stuck with my previous problem. I just unplugged my ("T" style) charger rather quickly by pulling straight up on the chord and my screen immediately went black on the first try.

Occasionally I'll find a folder of "Recovered Files" in the Trash after starting back up, but it wasn't there this time. When it is there, it's usually just a bunch of preference files and maybe some .xml files or something, but all seems to be working fine, regardless. I don't even have to be running any of the apparently affected apps for the associated pref files to appear. I think that's a separate issue, though, since they're nowhere to be found in this instance.

 

[GGJstudios]

Would calibrating after a SMC reset be of any more benefit than if it were calibrated prior to the reset?

No, it shouldn't matter. What's your battery condition and health? iStat Pro will give you readings on this.

 

[Karma Cheetah]

I'm a fan of iStat, but despite that, I have dashboard turned off since I never use it. Here's the info from System Report, though.

Charge Information:
Charge Remaining (mAh): 4052
Fully Charged: Yes
Charging: No
Full Charge Capacity (mAh): 4142
Health Information:
Cycle Count: 959
Condition: Replace Now
Battery Installed: Yes
Amperage (mA): -1857
Voltage (mV): 11976

And from coconut battery:

Current capacity: 4142 mAh
Design capacity: 6500 mAh

So, 4142/6500*100 = 63.7% design capacity

And some extra stuff, if it helps:

Age of your Mac: 29 Months
Battery temperature: 87.1ºF

As for the condition, it indicated "Service Battery" before resetting the SMC, but now reads "Replace Now," as I just found out, so the reset did have some effect. I didn't bring this up before as this has actually been a long-running problem that started while the battery condition was still "Normal." It's been more of an annoyance than a crippling malfunction, so it's been easy to ignore. I just replaced a fan, though, so I got in the mood of fixing/upgrading hardware where I could, and that includes this problem.

Point is, the battery condition was normal when the problem started, so I (possibly in error) assumed it was independent of the shutdown problem. Maybe one caused the other? I dunno, but hopefully I'll find out

Fun fact: 959 cycles/(29 months*30 days)= an average of 1.1 cycles per day. Maybe I use my laptop too much

 

[Karma Cheetah]

Breaking news: I got it to do it again. Last night, I tried unplugging/plugging the charger 10-20 times to try forcing a shutdown, but no luck. After leaving it plugged in overnight, I tried it again this morning and it shutdown the first time. So maybe how long it's been plugged in has something to do with it, which would imply it's possibly not purely a hardware problem?

I also read where in the battery-related version of my problem, the green battery level indicator lights on the side would be full before unplugging, but after the unexpected shutdown, only one would be lit up. I checked the same lights after this most recent shutdown and they're all full. Very confusing.

I'm thinking since my problem seems to be uncommon, it may be best to make a trip to the Apple store. I'm reluctant to do this since I'm a moderately successful DIY-er, but if that's the best course of action, I'm willing to bite the bullet. Theories? Advice?

 

[GGJstudios]

I'm thinking since my problem seems to be uncommon, it may be best to make a trip to the Apple store.

I think that's a wise decision.