Weird Laptop problem - anyone repair IT kit ?

Emp_Fab

I have a strange problem with my laptop.  I've never encountered this before on any of the kit I've worked on.  Basically, the battery died a few months back and I ordered a cheap replacement - which solved all the issues.  The day before yesterday, I left it on and it shutdown when the battery went completely flat.  Now, it won't charge.  I can boot it as long as the power lead AND battery are connected, but Windows (10) says "0% available (plugged in, not charging)".  The other weird thing is that it's running very slowly - and it's at the hardware level, as even going into the BIOS settings it's obvious that menu changes are much slower than normal.

It will not boot with the battery removed - which could be a model specific thing, but I've never personally seen that behaviour before on any laptop.  (It's a Lenovo Thinkpad L560).  I've reset the BIOS to defaults, removed the battery & charger from Device Manager (and several other suggestions from Google), but the problem remains.

I seem to remember there are a couple of IT techs on here - @Danny1969 ?  Has anyone ever seen this kind of thing ?

It all seems to point to a faulty cheap Chinese battery, but I'm at a loss trying to understand how this could slow the whole system down.  I'm also unaware of any laptops that won't boot with the battery removed when the mains adapter is connected.  Every other laptop I've had that the battery has died on will happily boot from just the mains adapter.

I've ran the internal diags and they find no faults.  Windows 10 Resource Monitor shows nothing hogging anything - CPU, RAM, Disk etc are all idling along nicely, yet the whole system behaves like it's flat out - e.g. opening File Explorer can take five seconds before anything appears on the screen.  Trying to ping a public server like 8.8.8.8 results in normal ping times but the text in the command window appears like it's being typed - slowly !

Anyone ?

fastonebaz

Often when power is reduced the cpu is throttled to reduce power consumption so my diagnosis is:

Cheap battery fail - sucking power as it's trying to charge but falling
Reduced cpu performance due to reduced power 
Slow OS especially animated windows features 

Phil_C

I am also going for the cheap battery being dud. 

I've replaced many a laptop battery for many clients, buy cheap buy twice has bitten me on the arse more than once. I always opt for genuine batteries now if I can. Or at least a decent OEM. 

I've found throughout my computer repair days, while some things are really extensively complex, sometimes it's just obvious lol

Also as Baz has said, struggling to charge will reduce CPU performance as the laptop is essentially on the brink of shutting itself down.

Emp_Fab

Ok.  Thanks guys.  I'll put in a warranty claim on the battery and see where we go from there.

It's still bothering me that it won't turn on without the battery installed though.  I've never seen a laptop fail to do that before (though my sample size of fiddling with laptops with dodgy batteries is very small).

Danny1969

It's hard to say without a proper gander of the board but since the problem started with a chinese  fake  battery I would guess the PM chip which handles power in \ charging and serial bus power is damaged. This chip communicates with a serial EEPROM in the battery and AND the charger which has volts  \ ground and an additional sense volts pin which again gets interrogated by the PM chip. All modern brands like Dell \ HP \ Lenovo use this system on their more expensive models because it gives better charging performance and better battery longevity. 

As you say it should boot happily with no battery installed. You have probably done a PM reset but if not remove battery, remove charger, remove cmos battery and press and hold power button down for 20 seconds. If that doesn't cure the fault then you might need another board. 

Snags

30 seconds on Lenovo kit, although I think the extra 10 are bonus seconds

Officially Lenovo tell you not to run with the battery detached, but I've never come across one that won't. 

prowla

Some machines are very pernickety about their batteries; I've had Dells which need the battery attached even if it is duff.

ToneControl

can you borrow a different battery to test it?

Emp_Fab

I think I might still have the old one somewhere.  I'll try that if I can put my hand on it.  I haven't done the PM reset @Danny1969 but I'll try it now.. 

Emp_Fab

I got a refund on the battery.  My next question is where can I get a good quality replacement?

What suppliers can I trust not to sell me cheap shit that will only last two minutes?

Or... Is paying more than the laptop is worth for a genuine OEM one the only solution?

Danny1969

PSA parts are pretty good ... they use LL Power and other respected OEM's 

HerrMetal

Depends how long you plan to continue to use the Thinkpad whether you want to gamble or get the real thing.  If you want the real thing then use https://www.lenovopartsales.com. Check the FRU part number on your existing L560 battery but I think it should be 00NY486 or 00NY488.   It shows as €58.38 for me but not sure what exchange rate will apply and then there will be VAT and shipping.

Emp_Fab

Lenovopartsales.com wanted a VAT number before it would let me order, so that's out.  PSA Parts have it - but it's £70 plus delivery.

I don't even know for sure if the battery is at fault !  It could be the laptop itself !

guitartango

Emp_Fab said:

Lenovopartsales.com wanted a VAT number before it would let me order, so that's out.  PSA Parts have it - but it's £70 plus delivery.

I don't even know for sure if the battery is at fault !  It could be the laptop itself !

Make or borrow a vat number  

boogieman

Order one off eBay from a company that has lots of decent reviews that go back a while, rather than 10 five star ones from the last month. 

Danny1969

Emp_Fab said:

Lenovopartsales.com wanted a VAT number before it would let me order, so that's out.  PSA Parts have it - but it's £70 plus delivery.

I don't even know for sure if the battery is at fault !  It could be the laptop itself !

I'm working in the shop tomorrow, give me the FRU off your battery and I'll see if there's one out the back in the pile of used batteries we have. 

I wouldn't buy one at this point because the machine should post without one

Emp_Fab

Ah.


I’ve only just read your post.


I’ve ordered a used (supposedly genuine) one off eBay for £30.  If it doesn’t fix the issue, I can return it at my expense within 14 days, so no great risk really.

I am bothered that it won’t show any signs of life other than three flashes of the power button when plugging the mains in without the battery attached.  It does the same WITH the battery in but also boots (and runs very slowly).  No battery = no boot or POST.

I’ve never come across a laptop that won’t boot off mains adapter only before - so it could be a mainboard fault.

I can get a fixed price repair on that for £70 though if it comes to it.  It’s not the newest machine, just an i5-6200 with 8GB ram and a Samsung Evo 500GB SSD, but it’s fast enough for me and the screen (very recently replaced) is great.  None of my other laptops are anywhere as nice.

Not that’s it makes any odds now, but to answer your question, it’s a 00NY486 / 71+ / 4X50K14089.

57Deluxe

remove power AC, remove battery and memory overnight. Press the power button ON for 30 secs in this sate. Silly as it sounds, some design on board are suseptable to a capacitor getting overcharged and blocks rebooting/battery charging  - often when Hibernation option has been used.

Other than that, just get another cheap battery many are just a tenner now, Not all cheap are bad expect 20% failure from experience. I remember the days of Compaq and IBM batteries being £230 !!

Emp_Fab

Bollocks.  The replacement battery arrived and it's made no difference - so it's got to be the motherboard.

My electronic skills are not good enough to attempt a repair.  Well - I could, if I had some remote assistance as I have a fair bit of testing and SMD soldering kit - I just don't have enough knowledge to attempt it without a schematic showing test point voltages / waveforms.

I've found a repairer in Colchester that does fixed-price repairs for £75 - which I'm considering.  Anyone have any other ideas ?

Snags

A £30 off Ebay job is not genuine, unless it's used, in which case it could be shagged.

Like Danny, I've got a pile of pre-loved Thinkpad batteries at work. An FRU or the exact model of the laptop makes it easy to see if we can bung you one (or the number in the red circle on the battery if it has one,  as they span multiple FRUs).

Danny1969

The hardest part in working through at component level is actually identifying  what a component actually is. Some are far from obvious, what looks like an 8 pin DIL IC is often just a switching Mosfet in a DIL package with the drain and gate shorted to multiple pins for better current handling. Some little black blobs could be inductors, could be resistors, if your lucky the board will have legends as in Q = transistor, L = inductor, R and C are obvious D for diode etc. Here's some tricks you can try

Basically on a laptop board it's 16 to 19V in but there will be buck convertors all over the board to generate the different lower voltages needed .... 3 volt ish for CPU, 5V for serial bus, 9 to 14V or more for battery charging. A buck convertor just switches current across an inductor and cap then smooths out the average. 10V switched into 10 equal on \ off cycles and smoothed will average out at 5V output ... then the pulse width is adjusted for higher lower voltages. Very simple but effective

Always start with a good visual under magnification. I use around X6 and check both sides of the board after blowing with compressed air. I've know a sliver of silver foil from a Kit Kat wrapper stop a board booting so have a good look

Spray some alcohol on the board, apply power with the battery connected .... watch the board, does one area dry quicker than another ?, this can help track down a shorted diode or other component that's drawing too much current and not letting it's buck convertor start. The switching MOSFET in the smaller BC's will look like a 8 pin DIL (like an opamp) on the larger ones it will be more obvious. The little chip that generally controls the charging and other things is often made by Maxim and it's a tiny bugger with either legs all the way round or more recently BGA underneath. Often when a battery damages the chip a sliver of the top will come off due to the internal heat surge. Unfortunately these are difficult to change, if you see damage on this chip it's game over for DIY 

If no obvious component is pointing to trouble then my normal next step is to start buzzing things through with a meter. Check diodes both ways, make sure what you think is an inductor isn't a shorted capacitor and vise versa ... You can get lucky and actually find an SM fuse ... these are often white or red and marked with F on the better boards. Often though you can spend hours and have to admit defeat in the end. My rule of thumb is I'll spend an hour on a board for £25 and within that time I'll fix it and charge £50 or it's BER for £25.

Your guy at £75 sounds quite reasonable to me