Inspiron 1545 Battery charging issue

Elemdee

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This is the laptop repair that never ends. It came to me for a dc jack replacement. Done. This model has multiple charger ends and I matched the cord end by purchasing this: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=220581921906&ssPageName=STRK:MEWNX:IT (probably inconsequential information but I'm throwing it in anyway for your reading pleasure.)

The laptop receives power fine without the battery in. However, with the battery in, the front power light starts out solid white, then it seems to go through some sort of process, then determines that it will not recognize the adapter cord, and then the front power light will blink 4 orange and 1 white from then on. The Bios tells me that the battery health is normal but the AC adapter=Unknown. It will not charge the battery.

The very first time I booted I received the following on the screen:

The AC power adapter wattage and type cannot be determined
The battery may not charge
The system will adjust the performance to match the power available
Please connect a Dell 65W AC adapter or greater for best system performance
To resolve this issue, try to reseat the power adapter.
Strike the F3 key (before the F1 or F2 key) if you do not want to see
Power warning messages again.
Strike the F1 key to continue. F2 to run the setup utility
Press F5 to run onboard diagnostics.


The power adapter is a PA-21 which is 65W and original with the PC.

Could it be that I didn't properly solder one of the 8 tiny contacts on the jack and therefore it's misreading or do any of you think something else could be going on? The jack did fit snugly well in the holes and I thought I did well with the solder but ya never know.

I found one mention of this on the Dell forums but the response was so blah blah blah it didn't make sense so I came to you guys, my Technibblets. <3 ;) HELP!
 
The center pin connection is your problem. It could be the charger, the charger's cable, the new DC jack work, or something damaged on the motherboard.

That center pin connection doesn't supply regular voltage for charging, it's actually a communications line from the laptop to the charger. If that's damaged or not working, the laptop will refuse to charge the battery and claim that it doesn't know what kind of charger you're using.
 
The center pin connection is your problem. It could be the charger, the charger's cable, the new DC jack work, or something damaged on the motherboard.

That center pin connection doesn't supply regular voltage for charging, it's actually a communications line from the laptop to the charger. If that's damaged or not working, the laptop will refuse to charge the battery and claim that it doesn't know what kind of charger you're using.

I tried a universal charger on it with 2 different tips and got the same orange blinking light response with both so for the moment I'm going to rule out the charger and the charger's cable. I guess I will dive back in and redo the solder job and see what comes of it.
 
Does the chargers you tried have a center pin? I know a lot of generic Dell chargers don't and this problem is quite common. My pin fell out of my charger and now mine doesn't charge anymore.
 
You either didn't solder the middle pin correctly in the Laptop or the Adapter needs to be replaced.

Sadly, it needs to be replaced with an OEM one. I am not aware, offhand, any third-party charger that fakes the center pin.

Dell with this center pin is being a bitch. It is essentially the same as chips on ink cartridges.

I will be doing one of these either Tomorrow or Monday, depending on when the jack comes in. Thanks for giving me something to look forward to :P
 
Yep, the customer's charger has a center pin, as well as the 2 tips I tried with the universal. I'm really hoping I didn't solder it right, because she didn't have this problem with the old jack. I didn't have the heart to open this thing up tonight. Going to sleep on it and tackle it in the a.m.
 
I read about a very similar and apparently quite a common fault to this the other week while troubleshooting a dell inspiron that powered on fine while on battery but refuses to even POST with the charger plugged in.

The post said that while diagnosing the issue an external monitor was plugged in the problem went away - the issue in this case was with the ground on the DC jack (or one of the tracks to it on the board) - it transpired that by plugging in an external monitor it made the ground circuit and the charger was then recognised fine - maybe a long shot for your fault but worth checking the grounding on your dc jack just in case.

I've just searched my history but can't find the post, if i find the URL i'll post it here.
 
The universal adapter isn't going to work, even though it has the centre pin. It needs the circuitry that is incorporated into the dell adapter that tells the laptop that it's a Dell adapter. There is a good chance the customer's adapter has a broken recognition lead/circuit. Here's an illuminating article on Dell adapter recognition.

Have you tried a known-good Dell adapter?

Edit: The article describing the identification chip located in the adapter is here. Very interesting reading. The conclusion there is that the recognition wire in the adapter power cord likely picks up static electricity and zaps the recognition chip, buggering its memory-resident identification program. It could also be poor soldering on the DC jack, bad plug, bad jack or bad on-board controller that interrogates the recognition chip. Most likely, it's a zapped recognition chip. A new adapter would be required to fix that.
 
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The universal adapter isn't going to work, even though it has the centre pin. It needs the circuitry that is incorporated into the dell adapter that tells the laptop that it's a Dell adapter. There is a good chance the customer's adapter has a broken recognition lead/circuit. Here's an illuminating article on Dell adapter recognition.

Have you tried a known-good Dell adapter?

Edit: The article describing the identification chip located in the adapter is here. Very interesting reading. The conclusion there is that the recognition wire in the adapter power cord likely acts as an antenna, picks up static electricity and zaps the recognition chip, buggering its memory-resident identification program. It could also be poor soldering on the DC jack, bad plug, bad jack or bad on-board controller that interrogates the recognition chip. Most likely, it's a zapped recognition chip. A new adapter would be required to fix that.

Wow Larry, thank you for that terrific information! I did try 2 different known-good Dell adapters today, both are the same type as this one is. Couldn't try them until today because they were traveling with my husband and son. Same outcome. Desoldered and resoldered the jack today. Same outcome. Ordered another jack today from a different supplier, one that does jack repairs themselves and uses them. I am also considering asking that guy I met (and PM'd you about) if he would mind meeting with me and testing the board with me, I'd pay him and chalk this up as a learning experience.

Edit: You DO know what this means, don't you? Now I'll have to go to a recycler and find an old Dell adapter and pull it apart to play with it just for fun!
 
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Does anybody know whereabouts on the motherboard the circuitry that queries the charger is located? I am working on an Inspiron 1545 which has a daughter board for the DC jack. Is the identification circuitry on this daughter board or the motherboard itself? I ask because a known working charger is not being recognised and the daughter board has just been replaced due to a broken DC jack.
 
I wish I'd seen this thread 6 weeks ago.

I got a laptop with exactly the symptoms described by the OP. The identifying circuit is in the daughter board. I ended up with a replacement battery, power board and charger. All were compatibles from China any one of which had recognition issues if used with original Dell components.

The total cost of all 3 parts was still only 75% of the cost of a genuine Dell battery.


Sent from my HTC Desire using Tapatalk
 
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