Laptop not charging.

bz Inscribed thus:

Just a note: In the UK its not allowed/legal to do a repair where the integrity of the repaired item, in this case, the PSU is compromised such that it could be a hazard to health.

The PSU/brick case is welded together in order to prevent any attempt to repair it. Making a joint in the cable feeding the appliance is not considered safe.

Replacing the power connector on the end of the cable, if you can get one, would be allowed. Unfortunately the manufactures have gone to great lengths to prevent these from being available from any source.

I second these last comments !

The 3rd pin on a traditional Dell 19vdc 4500mah is a dummy. I'm using one on an Asus laptop that had the same requirements. Only thing you need to watch is using an underrated PSU as you probably will overtax it. Having more power capacity isn't an issue for obvious reasons. I'm also using an HP 19vdc supply on a Toshiby. All these have similar CPU configurations and requirements within +- 10%.

The plot thickens!

I'd have to say once I've checked the plug / socket fit, polarity and current rating I have also done a bit of mix-n-match with no ill effects (that I know of course).

Daughters old Dell Latitude D520 came to me with a genuine Dell PSU but possibly the lower rated one of the two (65W V 90W etc?). Wouldn't these power supplies be current limited to their maximum continuous rated output so apart from it running hot, shouldn't put them outside their design parameters?

Wouldn't less current being available at the charger just mean the laptop takes longer to charge, or not power the laptop and a dock and an aux battery etc?

Indeed and would be my preferred scenario.

Daughters D520 stopped charging the main battery but seems to still charge the aux battery (in the CD bay) ok.

So, I picked up another battery that seems to power the thing ok but still isn't charging, presumably pointing to the charger or charging circuitry in the laptop itself (that charger was supporting both batteries for a year or so).

I have ordered a Targus universal (90W) charger in any case (for general use) so can use that to see if it's the charger at least (data pins permitting etc). ;-(

Cheers, T i m

I don't know for absolute certainty since I've never pushed the envelope but an underrated laptop PSU is going to work harder than it is designed to. This rationally leads to a premature failure. Consider the analogy of an underrated PSU in a desktop computer similar.

That's the bit I'm unsure on. Ok $100 question could be 'are they short cct protected? Something that limits it's output to a design maximum can't theoretically be 'overloaded' can it?

Whilst I'm sure you are right in many things I'm not (yet) sure it's always the case with all these things. ;-)

Other than the load on a desktop PSU is a direct thing whereas the load on a laptop PSU may depend on what it's doing at the time. ie, Charging and running, or just running etc. I have noticed that on many battery powered devices it often says it will take longer to charge the battery if the device is turned on at the time. Is this down to the heat of running the device /and/ charging the battery or the fact the chargers can't generally do both to full power?

As I said, I'm not advocating an underrated PSU for anything, just that there could be 'nearly enough to do it all and cope ok', 'enough to do it all' and 'more than enough' (and let's hope there aren't any shorts on here). ;-)

Cheers, T i m

p.s. Daughters (technically) 'smaller than it could take' PSU only ever runs warm. The one powering our TV runs much hotter.

Update:

A replacement primary battery came today for daughters Latitude D520 and when I fitted it the BIOS Battery Info screen when from 'not installed' (empty bay or with the old battery fitted) to 'Discharging' with the new battery so that was something. ;-)

Then I found a faulty 90W Dell adaptor I had kicking about and when I powered it up it made a noise like it was trying but didn't light the LED nor put any voltage on the output plug. With both daughters and this charger disconnected from the mains and after insuring there was no output voltage I measured the output resistance on both and found the 'dead' one to be shorted (good one about 200 ohms).

With nothing to lose I carefully cut it open the duff adaptor and after a bit of experimenting concluded the short was in the cable as it exits the power brick. With a decent iron and de soldering pump I removed the iffy output lead, trimmed it a few inches shorter and re heat-shrunk and connected the cables. I put it back in it's case, taped it up and powered it up, LED on and 19V on the output. ;-)

Plugged it into the D520, "AC Adaptor = 90W' and the primary battery status changed to 'Charging'. ;-)

So the D520 looked like it had two faults, a dead primary battery and faulty ID function (I'll check that one out tomorrow). It also seems the modular bay battery isn't so fussy about the PSU and has been charging and working ok.

We then tried the same 'test' PSU in daughters b/fs not-charging Inspiron 1545 and it also now detects the charger but didn't seem to want to start to charge. He says the battery had about 2hrs life before it stopped charging. A mate has a 1545 so we will try his battery in this one before doing anything further.

I'll provide another update as / when we know anything on that.

As the round plug from the D520 adaptor fits the octagonal socket on the 1545 I may get a pair of genuine Dell 90W adaptors with round plugs as they can both use either.

Thanks again to all those who have offered help / feedback on this so far.

Cheers, T i m

Hi Tim, T i m Inscribed thus:

Sounds like the protection circuits in the battery killed the feed to charge it. If you decide to investigate you will probably find that one or more cells has died.

That sounds right for a good adaptor.

Sounds good ! I bet you've done this before... ;-)

Yea, a result !

Thanks for this update ! Its nice to know.

OK, now we are back online with a new battery I may well have a closer look. I understand it wasn't lasting very long before it failed but the presence of the modular battery masked it a bit.

Indeed, with all sorts of stuff (I feel if it's already 'broken' you have little to lose). I have always got more fun out of fixing something then using it than just going out and buying it / a new one. years ago I designed, built and ran my own mobile disco (for my own pleasure really ). 1.5kw 3 way stereo PA, console with mixer, 8 channel light sequencer (before you could easily buy such things), strobe and all the speaker cabs etc. I drove it about in a Morris Minor van that I bought for £25 and put another gearbox in at the car park where I bought it before I could drive it home. ;-) [1]

A result indeed . She likes the D520 and was happy to carry on with it even as it was. We /could/ get her something else but this laptop does have a nice substantial feel to it so we are all happy it's fully working again. [2] The replacement battery ran for 3 hours this morning and the modular battery is at least 80% good.

My pleasure. So, we took his laptop to my mates PC show and were lucky to have the chance to try all different combinations of laptop, battery and charger.

The first smile was to see a known good battery and charger in his lappy charging AOk (so all the charging circuitry was ok ). The second was later back at home when my multifunction charger arrived from eBay and was 'seen' by the Dells as a 90W adaptor. The cherry on the cake was when he left the Targus connected and after about an hour mentioned that his presumed 'dead' battery was now showing 14% charge. Left it slowly rose to 100% and he's currently running it down and has run about 40 mins with 20 left.

I' thin opened the original chargers for both machines and both had broken data wires at the plug end. I have 3 on their way at a fiver each and if they work they will be cheap genuine chargers. ;-)

I found this very interesting on Youtube (very well put together as well):

We picked up a clone Dell charger that seems to advertise it's a 150W device (it isn't, it's a 90W). Maybe someone found a batch of unwanted chips or thought that responding with '150W' would make more kit happy?

Cheers, T i m

T i m Inscribed thus:

You sound a bit like someone else I used to know. He did something similar... with a van.

I presume you mean the chargers and not the plugs for them. I've yet to find a source for the 3 wire plug.

I agree ! very interesting. It answers a couple of questions.

Sounds like someone has doctored the unit.

Those washing machines with the plastic tubs are quite straight forward to replace the bearings in. In fact I may still have a repair kit or two kicking around.

The hinges are a weak point. Check the screws and make sure that they are tight. If I recall there are three screws in each hinge bracket.

Take Care. The wind is wicked at the moment.

Sorry no, the output lead, strain relief bush and Dell 3 way tubular plug.

That's what I first looked for but took the lead assay as it probably wouldn't have been much in it price wise. Ordered yesterday, arrived today and I'm going in .... ;-)

I guess if it's easy to implement (one wire and two legs at the charger end) and cheap then I can see why they might.

It's a clone so who knows. [1]

Erm, plastic tubs yes, sealed (as in welded into one piece in the factory) I believe less so. /IF/ you could get the drum out through the mouth of the tub you would be ok but on these you can't. Ironically the tub halves (front and back) were actually designed to be bolted together with a gasket / seal but some bright spark suggested they could save 10 screws, a seal and assembly time to they were welded together after that. The typical 'repair' would be two new tub halves, the screws, seal (the bearings you were going to replace anyway) and I understand, different suspension mountings, hence the write-off (at 13 months).

Noted.

It is indeed and that seems to have blown daughter and b/f some work back up in Scotland as they are both tree surgeons. ;-)

Cheers, T i m

I've since ordered an external charger that should be ok for most of the Dell batteries so at least I can prove if it's the battery or the laptop.

T i m Inscribed thus:

Mmm. The ones I was thinking about have a series of metal spring clips around the perimeter of the tub. The bearings are essentially clamped in place between the lip on the inner side and a plate on the other with the shaft and pulley, its retaining bolt holding the lot together.

At least something good from the destruction caused by the wind.

They put these "one wire" interfaces into the batteries too !

I've have cheap Chinese made ones that wont charge in a Dell ! Which sounds a bit like the one you refer to above.

Ah no. Inner bearing fits up against the drum and into rear bearing mount from the front. Outer bearing from the outside held in place by the belt drive wheel and a nylock nut (bearing construction similar to a car road wheel hub etc).

Well, yes, I guess. Still not nice to profit from the miseries of others but there is still some 'good work' that can be done (clearing side roads / tracks / paths etc). When they were on their way back up last time the bridge was being washed away at Cockermouth. ;-(

No, really? ;-(

It does indeed. However, after Googling about it seems there may be some hope in a BIOS update? It's currently A2 and I think there is an A5 or 6 to be had. I just need a charged battery in there to do it. I've ordered an external charger as I'm told the pinout of most of the Dell batteries are the same (so it will cover a fair range of models and we have a few between us) in case I can't access another machine or a charged battery elsewhere.

Might as well do the easy / non-invasive things first. ;-)

Cheers, T i m

T i m Inscribed thus:

So I understand.

Yes but they put the connector block in different places on the battery pack ! You will have to let me know how it goes.

I couldn't agree more.

Ok ta. I've asked on the Dell n/g if anyone can confirm if this particular model / generation does so for sure, just in case it could be summat else.

Yeahbut this charger is what I would call more of a tech / service aid as the charging plug is floating on the end of a wire and (can be) held against the battery with a Velcro tie. This morning I used it to charge the battery from the Studio 1535 (and therefore was able to apply the BIOS update) and currently I'm seeing if it can wake up the old battery from daughter D510 Latitude (only to see if I / it can, I'm pretty sure it's pretty low capacity now).

So far I'd say pretty well, insofar as it has allowed me to update the BIOS and prove an unknown battery to be good even if not compatible with the laptop. ;-(

This 1 Wire stuff may well be there for good reason (?) but when charging up old laptops with basic two wire connections and NiCd/NiMH they just charge, even if they only last for 5 mins (enough time to act like a UPS). If they don't a bench PSU might get you started ...

I'm now looking to see if I can borrow a battery for the 1535 before I suggested they buy 'another/ batter but at least this time we will know what questions to ask. ;-)

Cheers, T i m

p.s. I was wondering just how the original Dell battery declared itself 'dead' and therefore, if I was to re-cell the original with the cells from the clone, will it be happy (or have the electronics now shut down for good)?

T i m wrote in news: snipped-for-privacy@4ax.com:

maybe it's better to buy generic laptops instead of name brands,and then you can use generic chargers and battery packs.

Assuming they all aren't going that way as has been suggested then yes I guess it would.

FWIW the only laptop I have ever bought new was a Compaq Contura and I think that may have been a 386. The rest were mostly given to me (broken) or sold cheap (low spec or with known faults) etc.

Daughters Dell Latitude came the cheap way (mate buys laptops by the pallet) with an unknown BIOS password but £20 and t'internet had that sorted. ;-)

Daughters b/f bought the Dell Inspiron 1545 new as did the owner of the Studio 1535 I'm looking at now and in light of the current issues I'm not sure if either would go that way again. However, how could you tell if a laptop used 'tied' components like this?

Also, I wonder what proportion of laptop buyers go looking for cheap replacement bits off eBay versus buying them straight off the manufacturers web site (and therefore never 'seeing the problems')?

IN the case of the Dells I have here atm I'm not sure any of the issues have said 'This is not a Dell battery / adaptor' but:

"This battery has experienced a permanent failure and needs to be replaced".

"Warning: The battery cannot be identified. This system will be unable to charge this battery"

.. and similar with the power adaptors.

So presumably those could still happen whoever's brand sticker was on the machine itself?

But yes, bring on the 'generic / modular' laptop (so it works more like desktop clones) where not just things like optical drives can be swapped between brands (and CPUs, RAM, HDDs etc) but system boards, chargers and batteries.

But then I have never seen why we need so many different cars, washing machines, TVs .....

Cheers, T i m

T i m Inscribed thus:

Good move !

Ah. I envisioned a unit that the battery was placed into rather than a connector on a flying lead. I would be interested in the pin out for that. :-)

I'm not at all sure ! The battery packs that I've taken apart have not had, what I would call "dead Cells" ! Usually there is one or two cells that have very low voltages compared to the others. I have tried to boost the voltage on the low ones without disconnecting the others, and found that they recover just fine. Even so the pack still will not charge though it will power the machine as normal. Beyond that I've not really had the inclination to investigate further.

As an aside I have a set of recovered cells happily powering an alarm bell, float charged from the regulated 12V supply.

Understood as that's how yer typical charger works. The fact that this charger is supposed to cope with near 'all' Dell batteries with the one connector and many other makes with different connectors made it all the more interesting. Apparently, if you get the connector on this model reversed (we were only talking about the Dell batteries at the time) nothing happens (good or bad). The previous model would release pixy smoke from somewhere. The guy also ok'd the idea of being able to supply the different ends as required and as available for about a fiver each.

When you power it up you get a single red LED on the (sealed) power 'brick'. Plug it into a (good) battery and the 4 green LEDs light up in sequence then extinguish (2 second cycle). Once the battery reaches

Well there is a 4 pin plug that goes into the brick and another 4 pin bigger connector in the middle of the short lead to the battery plug. The next time I get the DMM out .. ;-)

Similarly (and as much use I guess) would be the pinout of the cells to the connector, if I get to pull a pack apart?

Part of my doing all this is because (mostly) I like to understand what's going on behind the scenes (a classic being that Youtube 1 Wire power adaptor tutorial).

Exactly? ;-(

We would call that 'balancing' in the RC model racing game. ;-)

Oh. So there may be summat 'deeper' going on here. Like with some printers when they reach their nominal max print run limits?

I would if there was some logic and low cost to the process. Like if I was given a batch of known good cells and a few battery packs to strip down. Other than that it means a bit of gambling buying new cells and we aren't really in a position to do too much of that right now.

It can be done, sometimes. ;-)

Cheers, T i m

I did start going through the 6 cells with Ah measuring recycler but 'she' needed this working. So, as the lid goes flat I'm measuring the lowest voltage cell and replacing it with a known good one in the hope I'll end up with the best matched set. ;-)

T i m wrote in news: snipped-for-privacy@4ax.com:

I don't know.

different people want different features. I prefer small cars that handle well and have "ample accelleration",while others want armored tanks that ride like boats and seat half a dozen.

IMO,those "chipped" suppplies/battery packs are just an effort to monopolize their products,so you can't use generic chargers or battery packs and save money. The "generic" charger or battery pack just has it's internal ID chip programmed to suit a particular manufacturer,and a "brand name" tag applied,raising the price and profit margin.