hal48martin

The laptop was working fine. For no known reason the battery light came on and the laptop ran off of battery power until the battery fully discharged even though the AC power remained connected and on.

The power cord has been proven fine.

With the power cord plugged in and the battery installed there is no sign of life at all, no charging, and no light activity.

With the power cord plugged in and the battery removed the three lights on the front of the laptop flash green.

This seems to indicate that there is still an internal connection between the power connector and the battery. Does anyone know if it is reasonable to consider that the battery has failed (maybe shorted?) and that replacing the battery should solve my problem?

Thanks for any input,
Hal

TheMatt

At first it sounded like a broken solder connection between the DC jack and the motherboard, but its strange that it receives power with the AC power in and the battery out. Can you at least turn the laptop on with it like this?

hal48martin

Matt,

Thanks for reply. I am very detailed when I look at something so although what I said in the begining is right things have changed a little now. Currently the green lights flash when the battery is in and when it is out but I can not power the unit on at all. The AC/DC converter is cold so I conclude that there must be only enough power consumption to turn on the lights. It seems that power is getting distributed internally to the laptop since the lights are flashing, but the battery is not charging nor am I able to power up the unit at all. When the problem first occured the laptop ran fine until the battery totally lost its charge and then nothing at all. Then I found that the lights flashed green when I removed the battery. I removed and installed the battery several times with lights flashing without battery and no lights with battery. And now lights flash with and without battery but absloutely no battery change nor ability to power on the laptop.

I need any ideas that you have as I am confused.

Best regards,

Hal

TheMatt

Do you have a multimeter or voltmeter you can use to test the power supply? That is a quick and easy way to test if the power supply is functioning.

hal48martin

I know that the power is being delivered from the DC converter to the laptop. Where is a good place to test it internally to the laptop? At the battery connector? Should I take the cover off?

Thanks for help,

Hal

TheMatt

Just curious, but how do you know the power is getting there? Even if the laptop lights up with AC power but no battery, the voltage could be out of range.

The only real way to test the connection is to use a multimeter and do a continuity (or resistance) check on the CD jack and the solder point on the motherboard. This requires disassembling the laptop.

hal48martin

Good question... I have measured voltage on the tip and ring of the AC/DC converter cord (I guess that this is not under load though), and I have used a different power cord with same results on the broken unit and have used the broken unit cord on my other Dell with good results. I know that this can be misleading so I will do as you suggest and test internal to the unit.

Thanks again and stay tuned,
Hal

hal48martin

Here is the latest. The laptop is apart and I am able to measure voltages. I am measure 17V across the tip and ring of the cord before I plug it in and 0V across power and ground of the on-board battery connector before plugging in the cord (without battery). After plugging in the cord I only measure 1.3V across power and ground of the on-board connector. I am able to measue a short between ground on the battery connector and ground on the cord connector but nothing between the power connections. I am not sure if there are components in this connection or the cord power should be a direct connect to charge the battery? It would be dificult for me to break the computer down further so hopefully I won't have to. What would you suggest next? Is there something that I can do to troubleshoot the problem further, is it worth taking to a repair shop?

Thanks for your help,

Hal

TheMatt

Thats interesting.

How much resistance in Ohms do you measure between the positive voltage (the center pin on the external DC jack) and the positive connection on the motherboard?

hal48martin

Well, I think that it is open but I have to admit I am not sure what I am measuring anymore. The power connector on the compuer has a hole in the middle, a plastic space, and a cylinder that slides in (not so good a discription but you probably know what I mean). I assumed that the center was power and that everything around it was ground. If I measure between the center post and power on the battery connector it appears to be open, ground on the battery connector seems to be grounded. There seems to be between 17V and 19V on the power input and about 1.3V across the battery connector input when power is plugges in. Can you explain the AC/DC power connector? If I look at the on-board side there is a hole in the middle, and a cylinder with connection on the inside and outsie of the cylinder. where is power and where is ground? I know that I keep saying tip and ring but this is from a past life... what am I really looking at here?

Thanks,
Hal

TheMatt

You are correct, the center is positive voltage and the outside is ground.

Do you see the place on the motherboard where the DC jack is connected (should be solder there).

hal48martin

Yes, I can see it but can't really get too it without taking many more parts out.

What do you suggest?

Thanks,
Hal

TheMatt

If you can't get to it to test it then you probably can't get to it to fix it. I would take it to a local shop and have them do the repair.

blkudera

Hey there- I am actually having the exact same problem that you describe with the exact same model.

My battery stopped charging despite the attempts to use the AC Adapter from my other dell laptop that works just fine.

Obviously, the computer eventually died.

-When I try to power it on without the AC Adapter plugged in nothing happens.
-When I plug in the AC Adapter the two outside lights blink non-stop (the power LED and the battery LED.) Unfortunately I cannot find anything in the user manual or online at Dell to diagnose these blink codes.

Apart from your description, I think the power LED is yellow where as the battery LED is an amber color.

Here's the kicker- I just got the laptop back from Dell's repair shop where they indicate they 'repaired' the system board, fan, and heat-sink.

The power evidentially is not getting to the battery to charge the battery and is not getting where it needs to go to be powered on. It is getting to the blinking LED's, however.

Have you figured anything out? I would prefer not to hassle with Dell again...

Thanks!

hal48martin

You have described the exact same problem. I broke the unit down as far as I could and still get it back together. I am fairly sure there is eihter a cold solder joint or broken component in the power circuit to the battery. I gave up and took it to the local shop. I will let you know the results.

Take care,
Hal

blkudera

Hey hal48martin guess what- I tried to plug in the AC Adapter into my 5160 this morning and the battery LED only came on- and didn't blink. At that point I tried to power it on and it now powers up. Bizarre. Also, the battery appears to be charging while I have it powered on.

It lasted for about two minutes and then displayed the same behaviors as above. This is now the second time it has instantly died on me, and both times occurred immediately after trying to install some windows updates to Microsoft Office 2003. I doubt that is related in any way, shape, or form but I would be curious to know if I will be able to replicate this for a third time- maybe tomorrow morning.

hal48martin

I suspect that a component in the power circuit is on the edge. I will let you know what I find out.

blkudera

As it turns out I was not able to duplicate my efforts previously posted. However, I tapped the bottom of my laptop around a bit and it turned on and the battery is charging and has been running ever since. This is a spare laptop so I haven't been doing a whole lot with it- I presume once I heavily use it and get that processor fan spinning it might die on me again.

kraut724

ive been having a AC Jack problem with my 5160 for about a year now, i had it fixed once because DELL wouldnt touch it without charging me for almost what a new laptop cost. I had the AC Jack repaired at a shop but it got loose again from extreme heat. The second time i fixed it myself by just resoldering the AC Jack. Its now messed up again but this time the Motherboard is crapped out.

Heres the thing, I asked Dells tech support about my current problem, and by some miracle they are replacing my motherboard and my AC Adapter free of charge??

I SAID FREE!!!!!

There has been talk of a Class Action Lawsuit against them for these problems so maybe they have decided to bite the bullet to keep customers happy.

nbrepairs

Yea, you said free lol. And yes, there is a lawfirm in california that has been building a database of consumers who own the 1100, 1150, 5150 and 5160's. Least I think those were the four if memory serves me.

I'm a tech for a local shop here in Atlanta, and I also do laptop repairs on the side. And have seen my share of the above mentioned models. As well as a Latitude L100 recently. All seem to share pretty much the same internal components, motherboards, heatsink, etc.. And all seem to suffer from some of the same problems.

I have managed to repair some of these using a few tips I have picked up from here and there. Sometimes the DC Jack needs to be resoldered. Sometimes there is a bad ground coming off the jack. Simply fixed by soldering in a jumper wire from the ground pin of the jack to a local ground somewhere else on mainboard. Though that particular fix wont fix the flashing led problems.

Also, on some models, you will find a chip just below the "C" cover. Where one of the tabs from the cover itself is putting pressure on that chip. And over time, a few pins on that chip will break free from the mainboard where they are soldered. This will cause itermittent power problems. Such as the laptop suddenly shutting off when you go to move it or bump it. I have succesfully resoldered a few of these. Eventually, Dell revised the tab in question on the "C" cover and shortened it. Note, some models won't even have the chip in the same location (motherboard revisions I suppose).

Even though you might get the proper voltage readings from the tip of your power adapter, a load test is the only way to know for sure. Simply use it on another identical laptop, if it works there, then that rules out your power adapter being your problem. More than likely it will be one of the above issues. And in more cases than none, the motherboard needs to be replaced or repaired. I have yet to determine or find out from someone who knows, exactly which components are failing on these boards. But I am thinking it has something to do with the direct heat from the heat pipe off the cpu that sits quite close to unprotected, surface mounted components. Be it a capacitor or possibly an 8 pin DIP. I would like to find someone who happens to know which parts are failing.

It's a wide spread issue among this family of laptops. Dell knows it too. The 5160's were allready settled on according to that lawfirm in California. And I think your window for repair or reimbursement for repairs has allready passed. The other 3 models are still pending.

Not sure why the latitude L100 wasn't included. Has the same motherboard in it, same problems. Have an L100 here now, the power and battery led's on the front continuously flash every second or so. Maybe a bad timer chip in the dc circuit, who knows. But this one isnt the jack or a bad adapter or a bad ground. Gonna need a mainboard or get repaired by someone who knows which parts on the board to replace.

Chuck