Take a look at our
ThinkPads.com HOME PAGE
For those who might want to contribute to the blog, start here: Editors Alley Topic
Then contact Bill with a Private Message

T480 won't power on - in need of troubleshooting ideas

T430-T490, T530-T590 Series
Post Reply
Message
Author
bbgonda
Posts: 2
Joined: Tue Jun 21, 2022 1:03 pm
Location: Toronto, Canada

T480 won't power on - in need of troubleshooting ideas

#1 Post by bbgonda » Tue Jun 21, 2022 1:07 pm

Hi all,

This is my first time posting on this forum though I've been an avid reader of it for years. I'm stumped and would like to seek your guidance. I picked up a T480 that won't turn on. I knew this was the case and I wanted to see what I could do. I'd love to be able to give life to this wonderful model and perhaps gift it to my mother. So far I've been unsuccessful.

It came with no RAM, batteries, SSD, and power cord, which I added to cover all angles. I've also done a complete power drain, removed replaced the CMOS battery and even the power button board, which required a complete mobo disassembly to get underneath it. What I get at most is the power button light flashing a few times when I plug in the AC adapter (either on battery, or with no batteries when I've just unplugged and replugged the CMOS battery). When the CMOS battery is reset I also get some more lights turning on momentarily on the upper left of the keyboard. When plugged in with batteries installed, it will charge the batteries no problem and you can see the lights by both the USB-C and the TB3 ports going from orange to white, whichever port you us. That's about it. No noises, no fan spinning, nothing on the screen.

Short of replacing the mobo, I don't see what else I can do at this point, but perhaps I'm missing something, which is why I'm posting here. I considered swapping out the mobo from my own T480 and testing it but I don't want to fry my mobo if there are some other issues with this laptop. It's not difficult disassembling the mobo but there's always a risk of damaging something (some wire) so I'd rather not be so invasive with my daily driver if I don't have to be. Perhaps the only option is to purchase a new mobo and go for it, but first I thought I'd post on here. Any ideas would be very much appreciated. Thank you in advance.
X250, T460, T560, T480

RealBlackStuff
Admin Emeritus
Admin Emeritus
Posts: 22867
Joined: Mon Sep 18, 2006 5:17 am
Location: Loch Garman, Éire
Contact:

Re: T480 won't power on - in need of troubleshooting ideas

#2 Post by RealBlackStuff » Tue Jun 21, 2022 11:11 pm

Welcome to the Forum.
Did you put in the correct RAM (DDR4-2400 or 2666)?
Does an external monitor work?
Try to get into BIOS without an SSD in it?
Lovely day for a Guinness! (The Real Black Stuff)
IBM: T23 (XP/SP3) - Lenovo: X240, X250, T440p, M900 Tiny (all with W7/SP1)

bbgonda
Posts: 2
Joined: Tue Jun 21, 2022 1:03 pm
Location: Toronto, Canada

Re: T480 won't power on - in need of troubleshooting ideas

#3 Post by bbgonda » Wed Jun 22, 2022 11:19 am

Thank you for the welcome and for the suggestions. The answer is yes, I've tried them all. The problem is one I've never encountered: the laptop won't turn on at all as mentioned, so connecting to an external monitor won't do anything, and I can't get into the BIOS. The most I get is a few lights (power button and a few of the keyboard keys) flashing momentarily when plugged in, even after a CMOS battery replacement or disconnection/re-connection. I've tried both RAM slots using the very same RAM in my own T480. I'm stumped and don't want to have to shell out $200-250 for a new motherboard if there's something I'm missing. There's also no guarantee a new mobo will make it work. One option is installing the working mobo from my own T480, which is easy enough, but I prefer not to do anything so invasive to my daily driver given I use it for work every day.
X250, T460, T560, T480

RealBlackStuff
Admin Emeritus
Admin Emeritus
Posts: 22867
Joined: Mon Sep 18, 2006 5:17 am
Location: Loch Garman, Éire
Contact:

Re: T480 won't power on - in need of troubleshooting ideas

#4 Post by RealBlackStuff » Thu Jun 23, 2022 12:14 am

First get the T480 schematics: https://elektrotanya.com/lenovo_thinkpa ... nload.html
I assume you have the HMM already, but just in case: https://download.lenovo.com/pccbbs/mobi ... hmm_en.pdf

The only way to test this would be to strip it down to the bare essentials: motherboard/CPU, fan, only 1 RAM, keyboard, working external monitor, charger.
I'm not familiar with the T480, so perhaps a few more parts are needed, such as that power button board.
Make a drawing with screw locations of the bottom and insides of the laptop, and tape each screw to its drawing-location.

Once you have the mobo out, use a multimeter to measure all the Fuses for continuity (beep).
They are marked F1, F2, F3 etc. on the schematics (and also on the mobo), but that will only give you a rough idea of the area they are in.
Start with obvious ones, such as charging circuit, batteries, LCD-connector.
If they all test OK, see if you can get the essentials going.
Let us know what happens.
Lovely day for a Guinness! (The Real Black Stuff)
IBM: T23 (XP/SP3) - Lenovo: X240, X250, T440p, M900 Tiny (all with W7/SP1)

Post Reply
  • Similar Topics
    Replies
    Views
    Last post

Return to “ThinkPad T430-T490 / T530-T590 Series”

Who is online

Users browsing this forum: No registered users and 7 guests