Fujitsu laptop screen flickering/flashing when charging

[fincoder]

I have a Fujitsu Lifebook E558 presented with flickering and flashing screen. This happens even in BIOS screen, but only when charging. Never happens when charger disconnected, or when charger is connected and battery is 98% charged or more.

This laptop was sold by me as a refurb, is still under the warranty I put on refurbs (no warranty left from my supplier). I received it from my supplier with a Toshiba charger which has the correct voltage/wattage/tip so I'm wondering if that has anything to do with it. I currently have no spare genuine Fujitsu chargers to test with, but I tried a Lenovo one that had the same voltage/wattage/tip and the same problem occurs. I'll be able to test with a Fujitsu charger some time next week, but I'm not confident that will solve it.

Installed the latest BIOS update, no change. Any ideas?

 

[GTP]

Do you have another battery you could try?
To me - it kinda sounds like the battery is under some type of duress while charging.
Can you remove the battery and just have the charger plugged in to test.?

 

[fincoder]

Can you remove the battery and just have the charger plugged in to test.?

Thanks for the suggestion. This was particularly easy to try because, despite being a relatively modern Intel 8th gen laptop, it has a removable battery with a simple clip like the good old days!

The screen flickering does not occur when the battery is removed. To me, that doesn't prove the battery is the problem as it could be the charging circuit on the mainboard.

While Fujitsu laptops are excellent machines, made in Japan, parts are harder to find due to them being relatively uncommon in Aus.

 

[GTP]

To me, that doesn't prove the battery is the problem as it could be the charging circuit on the mainboard.

IMHO It still could be the battery and if possible I would try a replacement battery. It may be faulty and is intermittently drawing less current than it should, causing the screen flicker.
You did state that the screen doesn't flicker when the battery is at 98% or better.
Correct me if I'm wrong please, but doesn't the laptop run on the battery while ever its attached?
I believe the charger keeps the battery charging/charged.
The screen is the heaviest power user so to my mind it makes sense.

 

[fincoder]

Correct me if I'm wrong please, but doesn't the laptop run on the battery while ever its attached?

I don't think so. I believe laptops always run from the mains power if connected, and the mains power also charges the battery if it needs it (e.g. when below 98% charge).

I've tried a spare LCD panel that has the same connector, but it's only 13" size (laptop is 15"). With the spare smaller screen connected that likely has lower power requirement, I only saw it flicker a couple of times. So that test doesn't tell me much either.

 

[britechguy]

Correct me if I'm wrong please, but doesn't the laptop run on the battery while ever its attached?

The answer to that is, "Some did, in the fairly distant past, but I don't know of any modern ones that do."

The ones that did in the distant past would not run, period, if the battery was pulled and the power adapter was attached and on. Most now will run entirely sans battery if the power adapter is attached and on.

Part of the reason for the "only charge to 80% then stop" feature is because so many laptops are used in a way that they're pseudo-desktops and constant charging, and to 100%, has a negative impact on battery life for lithium ion batteries. I'm waiting for technology that forces the use of a battery to run it down even when the power adapter is connected because batteries do need to be discharge cycled for maximum functional life.

 

[sapphirescales]

To me, that doesn't prove the battery is the problem as it could be the charging circuit on the mainboard.

That's definitely possible but in my experience a faulty battery is much more likely. They're not expensive. Pick one up from battdepot.com (a good trusted source of high quality batteries). You can return it if it doesn't fix the issue. You just have to eat the shipping both ways (about $20). But you don't even have to eat it. Talk to the client and ask if they're willing to take a risk on replacing the battery and that if it doesn't fix the issue all they'll have to pay for is the shipping for both ways. Alternatively you can ask if they even use their laptop on battery. A lot of people just use them as desktops. They might just want you to remove the battery.

 

[fincoder]

I got in another Fujitsu Lifebook, 14" one but the battery was the same. Swapped the battery over and the same thing happened on the original 15" Lifebook. The 14" Lifebook with the battery from the original 15" doesn't show the problem.

So it isn't a battery problem.

I've noticed sometimes the battery charging doesn't kick in (BatteryInfoView just shows AC Power but charge rate zero), I think that's just normal battery management as Brian said above. But it explains why my refurb supplier, and me installing the OS/drivers/updates, didn't notice the problem. The customer didn't return it until several months after purchase, he saw the problem early on but because it went away (when charging wasn't occurring) didn't worry too much. I think recently he must have run down the battery enough so the flickering problem was occurring whenever plugged into AC, seemingly non stop. In my workshop I discovered it was perfectly fine again when charging stopped.

I'm going to have to replace (or refund) the refurb laptop for my customer (warranty). Not worth spending more time or money on. Maybe I'll sell it without a battery at a cheaper price.