16-inch MBP loses battery while plugged in

BOOMBA

macrumors 6502
Original poster
Dec 27, 2001
253
42
Hey there,

so I was doing some rendering in Cinema 4D on my 16 inch MBP, and I noticed that even though it was plugged in, the battery level was going down.
It got to the point where after 2 hours it was around 20% or so.

I figured it was just working really hard, and I don't plan to be using it exclusively for rendering like that normally, so while I was surprised and a bit disappointed I was ok with it.

But then Yesterday I was playing Minecraft on it, and the same thing... battery level can't keep up. Not as bad as when rendering, but the fan was on the whole time and it was at maybe 40% after 3 hours or solid gaming.

The battery is fine when plugged in doing menial tasks like websurfing / Photoshop etc.

Any ideas? I have the graphics set to AUTO.

Thanks
 

bsbeamer

macrumors 68040
Sep 19, 2012
3,293
1,665
Using the Apple issued and included 96W charger, a docking station (like CalDigit TS3 Plus), or something else?

What is the info reported under About This Mac > System Report > Hardware > Power > AC Charger Information?

Mine with 96W charger states:

AC Charger Information:

Connected: Yes
ID: 0x7002
Wattage (W): 94
Family: 0xe000400a
Serial Number:
Name: 96W USB-C Power Adapter
Manufacturer: Apple Inc.
Hardware Version: 1.0
Firmware Version: 1070051
Charging: No
 

morze

macrumors member
Jun 17, 2019
66
54
I remember reading on another thread that if you are charging via the USB-C Digital AV Multiport Adapter, it's limited to 60w or something. So you have to plug it in direct.
 

jinnyman

macrumors 6502
Sep 2, 2011
442
425
Lincolnshire, IL
If that happened with included power adapter, then it's pretty disappointing. The power brick should be able to keep the battery level at the same level at least.
 

matram

macrumors 6502
Sep 18, 2011
304
123
Sweden
Get iStat menu and check power draw and power supplied or do as bsbeamer suggest.

The highest sustained power draw I have seen when fully loading the machine is 100W which is a few watts above what the charger can deliver, but it would esily last a whole day.

The discharge rate you are showing, a 40W discharge, indicates you are using a charger or a charging cable that does not support more than 60W. As morze says it could be the cable even if you are using the 96W charger.
 
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am2am

macrumors regular
Oct 15, 2011
186
76
I remember reading on another thread that if you are charging via the USB-C Digital AV Multiport Adapter, it's limited to 60w or something. So you have to plug it in direct.
Not true.
I am using it and it charges approx 92W through adapter (compared to 94W direct from apple charger)
 

MrGunnyPT

macrumors 6502a
Mar 23, 2017
867
556
Anything below 85W will cause it to reduce the battery while charging.

I have noticed while working with VMs that using anything below that will drive down the current battery level while plugged due to the amount of power you are pushing from both the CPU/RAM/dGPU
 

BOOMBA

macrumors 6502
Original poster
Dec 27, 2001
253
42
Using the Apple issued and included 96W charger, a docking station (like CalDigit TS3 Plus), or something else?

What is the info reported under About This Mac > System Report > Hardware > Power > AC Charger Information?

Mine with 96W charger states:

AC Charger Information:

Connected: Yes
ID: 0x7002
Wattage (W): 94
Family: 0xe000400a
Serial Number:
Name: 96W USB-C Power Adapter
Manufacturer: Apple Inc.
Hardware Version: 1.0
Firmware Version: 1070051
Charging: No
mine says the same I think
AC Charger Information:



Connected: Yes

ID: 0x7002

Wattage (W): 94

Family: 0xe000400a

Serial Number:

Name: 96W USB-C Power Adapter

Manufacturer: Apple Inc.

Hardware Version: 1.0

Firmware Version: 1070051

Charging: No
 

bsbeamer

macrumors 68040
Sep 19, 2012
3,293
1,665
What USB-C cable are you using?

I've been rendering on MBP16,1 all day with multiple monitors and eGPU. Battery hasn't dipped below 100% at all with 96W charger plugged in.
 

BOOMBA

macrumors 6502
Original poster
Dec 27, 2001
253
42
Sorry for the delay, as @bsbeamer guessed it was the cable.
I bought this Anker 100Watt charger as a second charger for work, and with it bought an Amazon Basics cable.
I did not realize that I was using that Amazon cable which is rated at 3A, instead of 5A with the Apple charger (I wanted a long cable). I bought another 5Amp Apple cable and both chargers keep the MBP running at 100%.

Although damn, the 16 MPB fan is loud... oh well.

thanks for the help.
 

tivoboy

macrumors 68040
May 15, 2005
3,120
205
Anyone have the issue where the MBP 16" loses power while NOT plugged in? And I don't mean a little but after three days not plugged in a 100% battery is at 0% and won't even start. That just shouldn't happen like that.
 

Hexley

macrumors 6502a
Jun 10, 2009
889
28
The Anker 100W charger you pointed to has a very big flaw pointed out by their end users.

It will output 100W on a single USB-C port so long as only that USB-C port is used and all other ports are unplugged.

When plugging other cables into it will cut the USB-C output to 50W.

A year ago I almost bought that Anker charger too but it was sold out for a few months so settled for Satechi 75W Dual Type-C PD Travel Charger before the 16" came out. Last week they came out with a 108W version of it.

The Zendure SuperPort 4: 100W USB-C Desktop Charger has a similar flaw to the Anker 100W charger.

Sorry for the delay, as @bsbeamer guessed it was the cable.
I bought this Anker 100Watt charger as a second charger for work, and with it bought an Amazon Basics cable.
I did not realize that I was using that Amazon cable which is rated at 3A, instead of 5A with the Apple charger (I wanted a long cable). I bought another 5Amp Apple cable and both chargers keep the MBP running at 100%.

Although damn, the 16 MPB fan is loud... oh well.

thanks for the help.
- - Post merged: - -

Anyone have the issue where the MBP 16" loses power while NOT plugged in? And I don't mean a little but after three days not plugged in a 100% battery is at 0% and won't even start. That just shouldn't happen like that.
Were you able to repeat this?
 
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jerryk

macrumors 603
Nov 3, 2011
5,347
2,632
SF Bay Area
This thread points out why people need to get certified 100W USB-C cables when connecting to Power supplies with over 60W (3A X 20V). By default regardless of the output of the charger and demands of the device, the charging will be limited to 60W unless the cable has the chips that tell the charger and device that that it supports 100W (5A X 20V).

In USB-C Power Delivery, the devices, chargers, and cables can communicate and decide what amount of power (voltage and current) the charger should send to the device.
 
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