MacBook Pro only charges with smaller MagSafe 60W

Question

My MacBook Pro 2.3ghz i7 mid-2012 stopped charging and the light on the charger doesn’t show up anymore.

I thought it was the MagSafe 85W and got a new one, but my MBP is still not charging. The light does not work on both the old and new 85W charger, and neither actually charge my MBP.

However, I have a smaller 60W MagSafe that works ok. The light comes on and it charges the MBP.

What could explain this?

The DC jack looks ok, but I wonder if that could be it? Or is it more likely to be a logic board problem?

UPDATE

I’ve also conformed this by using iStat - it shows that the 65W charger provides around 30W while both the 85W chargers do not show up at all.

UPDATE 2

I have also used pmset from the terminal window to check the power management. As suspected, both MagSafe 85W are not seen at all, it reports "no adapter attached". It only works with the MagSafe 60W.

The rawlog, with the MagSafe60W attached and then removed shows: AC; Charging; 57%; Cap=3748: FCC=6550; Design=6900; Time=2:02; 3028mA; Cycles=92/1000; Location=0; Polled boot=05/12/19 08:19:07; Full=05/12/19 09:15:17; User visible=05/12/19 09:18:17 05/12/19 09:18:31 No AC; Not Charging; 57%; Cap=3761: FCC=6550; Design=6900; Time=2:01; 3097mA; Cycles=92/1000; Location=0; Polled boot=05/12/19 08:19:07; Full=05/12/19 09:15:17; User visible=05/12/19 09:18:31

The rawlog with the same MagSafe 60W detached shows: No AC; Not Charging; 57%; Cap=3761: FCC=6550; Design=6900; Time=2:01; 3097mA; Cycles=92/1000; Location=0; Polled boot=05/12/19 08:19:07; Full=05/12/19 09:18:31; User visible=05/12/19 09:18:31

The only difference between the Magsafe 85W and the 60W is the output: - MagSafe 85W: output 18.5V, 4.6a - MagSafe 60W: output 16.5V, 3.6a

I have also replace the DC jack and still no luck.

Why on earth my laptop only works with the adapter that provides less voltage and amperage?

Answer 1

Try to do a SMC and PRAM reset.

SMC, amongst others, controls power management of your Mac. From https://support.apple.com/en-us/HT201295:

These symptoms might mean that an SMC reset is necessary:

• [...]
• The battery doesn't charge properly.

Answer 2

You may or may not get any useful information from pmset, but it takes virtually no effort, so why not?

• What is pmset? A command line utility for manipulating and viewing power management setttings under macos. Ref Wikipedia article

• You can access pmset from a terminal window. You can access the system manual for pmset by entering man pmset at the command line (type q to close the manual).

• The -g options for pmset will display potentially useful information, and do not require root/su privileges. You will be required to use root privileges with pmset to make changes to system settings, but that may not be necessary at this time.

• You may wish to try the following when your chargers are connected, and note the differences. The output below is from my MBP:

pmset -g ac
 Wattage = 86W
 Current = 4300mA
 Voltage = 20000mV
 AdapterID = 5718
 Manufacturer = Apple Inc.
 Serial String = C047*************       # * replaces a portion of this string
 Adapter Name = 87W USB-C Power Adapter
 Hardware Version = 1.0
 Firmware Version = 01070069
$

• You might also try monitoring the log for a bit to see if that turns up anything relevant:

$ pmset -g rawlog
pmset is in RAW logging mode now. Hit ctrl-c to exit.
 * Battery matched at registry = 7939
05/11/19 23:01:34
 AC; Not Charging; 99%; Cap=6154: FCC=6181; Design=6669; Time=0:00; 0mA; Cycles=286/1000; Location=0; 
 Polled boot=05/11/19 14:56:06; Full=05/11/19 22:54:49; User visible=05/11/19 23:00:49
05/11/19 23:03:49
 AC; Not Charging; 99%; Cap=6155: FCC=6181; Design=6669; Time=0:00; 0mA; Cycles=286/1000; Location=0; 
 Polled boot=05/11/19 14:56:06; Full=05/11/19 22:54:49; User visible=05/11/19 23:03:49

Note that the charger was connected to my MBP during this logging activity, but the battery showed 100% charged in the menu bar at the top of my monitor.

Finally, if you see anything in the pmset output that seems suspicious, please consider editing your question to include that. No promises any of this will help of course, but we'll certainly give it a try.

Answer 3

Do you have or can you download iStat Menus; then look at the DC In sensor with both adapters connected. I suspect the MagSafe connector on your Mac has detritus in it and needs to be cleaned.

Check how many watts of input are being provided with each adapter. The LED may not be changing because it can't transfer the expected amount of current and/or the sense pins have been damaged.

Please see How to reset a magsafe charger that doesn't charge macbook pro's battery?