Computer not turning on after a battery replacement

Question

Lenovo Yoga C930-13IKB

The Lenovo Yoga C930-13IKB is a 2-in-1 laptop that features a touchscreen, fingerprint reader, and tablet mode. The device comes with a Lenovo Active stylus pen, 65W AC adapter, 4 cell 60WHr Li-Polymer battery, and a quick start guide.

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eliasp02 @virtourist_1

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crwdns2931729:0crwdne2931729:0: masiku 6 agoDzi 23, 2025

crwdns2933897:0crwdne2933897:0

Computer not turning on after a battery replacement

So I did a battery swap, using an iFixit-purchased battery and following their procedure. Everything went smoothly. At no point was I worried that I had broken something. But when I went to power up and turn on the laptop, the whole thing refuses to turn on. Here's what I tried:

Plugged into a 60W USB-C charger: no signs of life.
Plugged into the 65W USB-C charger that came with the laptop: It does appear to charge - charging light showed orange, then eventually turned to white. I also verified with a USB meter, and it showed the computer drawing about 30W.
Pressing the power button, either on or off the charger, turns on the light on the power button, but there's no other signs of life.
Long press of the power button (10s, 30s, 1m) doesn't do anything.
I opened up the laptop and removed the battery. Did a long press on the power button. Plugged in to power without the battery installed. Put the battery back in and reseated the connector. No change in condition.
I plugged in a USB-C dongle. It seems to draw power, but otherwise no sign of life.
I plugged an HDMI cable into the USB-C dongle, in case there's a problem with the screen: no sign of life.
I tried turning on and off the keyboard backlight in various conditions: no sign of life.

Usually for startup, you press the power button and the fans kick on, the keyboard lights up, and the screen turns on. No sign of any of that.

crwdns2934089:0crwdne2934089:0 crwdns2934093:0crwdne2934093:0

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crwdns2889612:0crwdne2889612:0 1

crwdns2944067:08crwdne2944067:0

Lenovos have LCD self test:

Plug in AC and

Press Fn, left Ctrl, and the power button at the same time

(if it works you see a screen of each colour/black/white for a few seconds each)

At least you'll know then if its the screen or not...

crwdns2934271:0masiku 6 agoDzi 23, 2025crwdnd2934271:0 Darren Lucas crwdne2934271:0

@virtourist_1 have you let the battery charge up long enough? How many Amps is your computer drawing from the power supply?

crwdns2934271:0masiku 6 agoDzi 23, 2025crwdnd2934271:0 oldturkey03 crwdne2934271:0

@oldturkey03 Yeah, it seems sufficiently charged up. Currently reading 0.000-0.02A

crwdns2934271:0masiku 5 agoDzi 24, 2025crwdnd2934271:0 eliasp02 crwdne2934271:0

@virtourist_1 that is the amperage that your computer is drawing when you plug it in? where are you measuring that amperage?

crwdns2934271:0masiku 5 agoDzi 24, 2025crwdnd2934271:0 oldturkey03 crwdne2934271:0

@oldturkey03 Correct. Reading from an inline USB Volt/Current meter

crwdns2934271:0masiku 5 agoDzi 24, 2025crwdnd2934271:0 eliasp02 crwdne2934271:0

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crwdns2934285:0crwdne2934285:0

crwdns2933315:02crwdne2933315:0

Lenovos have LCD self test:

Plug in AC and

Press Fn, left Ctrl, and the power button at the same time

(if it works you see a screen of each colour/black/white for a few seconds each)

At least you'll know then if its the screen or not... — Darren Lucas
@virtourist_1 have you let the battery charge up long enough? How many Amps is your computer drawing from the power supply? — oldturkey03
@oldturkey03 Yeah, it seems sufficiently charged up. Currently reading 0.000-0.02A — eliasp02
@virtourist_1 that is the amperage that your computer is drawing when you plug it in? where are you measuring that amperage? — oldturkey03
@oldturkey03 Correct. Reading from an inline USB Volt/Current meter — eliasp02

score 1 · Answer 1 · 2025-04-25T19:23:35-07:00

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oldturkey03 @oldturkey03

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crwdns2931729:0crwdne2931729:0: masiku 4 agoDzi 25, 2025

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@virtourist_1 okay so it looks like your board is a C930-13IKB EYG70 NM-B741 and I do have the schematics for that. NM B741 EYG70 Motherboad Schematic Now we'll have to start somewhere, right? Start with the power fuse F1. First check for continuity and then you can check for voltage on the fuse. Are you okay with doing the measurements? I had to post this as an answer even knowing that it will be incomplete due to the picture. We can only post pictures in Answers or Question but not in comments. This may take a few pictures etc. so I will always update this as an ongoing answer until we either get your beast working again or we capitulate ;-)

Here is the service manual for your computer Lenovo Yoga C930 13IKB Hardware Maintenenace Manual your beast has a power board combined with the pen holder. Check the flex cable to make sure everything is still properly connected. Page 44 of the SM shows more

@virtourist_1 that means your board get power from the battery but we are not sure about getting power to the board yet. We are looking for the VIN rail.PU9 would be my next check. That is a battery controller. Measure the voltage on Pin 5 of PQ9 and pin 5 and 4 of PQ11 Check that with your battery disconnected and then connected.