DELL E6400 unknown charger, plugged in not charging

[rabsonnjala]

Hallo team i have a Dell lattitude E6400 LA3803P which display an unknown charger message when starting up and when I check in windows it shows plugged not charging,

i downloaded a schematic, im trying to follow PSID, the schematic indicates that it comes from pin no 2 of the DC jack to PL3 and so on but the problem is i cannot find PL3 and other components that follow on the actual motherboard,

Please help me attached is the schematic and a capture of the motherboard. Thanks

[Mod. Edit] Schematic -> https://www.badcaps.net/forum/showth...37#post1281137

[mon2]

Re: DELL E6400 unknown charger, plugged in not charging

Hi. Unable to find where the external adapter enters the board from the posted pics.

Suggest for you to attach the adapter and then post zoomed up pics of that area only. Do not power up the adapter but only want to see the mating connector.

PL3 will be a surface mount inductor (coil) that 0603 in size so it is not too large. As per my post earlier this week on a similar case, the ID pin must mate with the logic board's EC to permit the 1-wire communication between the 2 parties. Logic board will send out 1-wire commands on pin 2 of the adapter, then the adapter will reply back with details to identify the adapter.

Need closer but clear pics to hunt down the PL3 and related parts.

[Spider1211]

Re: DELL E6400 unknown charger, plugged in not charging

Are you using an original known good Dell power charger?

[rabsonnjala]

Re: DELL E6400 unknown charger, plugged in not charging

Are you using an original known good Dell power charger?

Yes I have tried 2 original chargers they are not working on this machine but if I try on a different laptop, the other laptop charges without any problem

[ACS-Repair]

Re: DELL E6400 unknown charger, plugged in not charging

There is something about the AC adapter that the computer does not like. I've seen this before with Dell. Is the charger you are using the one specified for it or is it just an older Dell unit, maybe even with an adapter? In my case I was using an HP adapter, but when I connected the newer Dell,it worked OK.

[reformatt]

Re: DELL E6400 unknown charger, plugged in not charging

Dell chargers have a pre-programmed one wire IC in them that derives power from the data line (they call it parasitic power). When the chip is powered up initially, you see a short burst of data to the host which identifies what the charger specs are etc. So at the very least you need 3.3V on this pin from the laptop end. So measure pin 2 to ensure there are volts there and make sure that it's continuous to the ports centre pin as well. Put a scope on this line to see if you see the data then trace it from there back to the EC.

Note that abscence of this signal will result in the battery not charging and the CPU being throttled to it's slowest speed in some of the Dell's I've worked on (PROCHOT gets triggered in this event).

BTW, these one wire IC's usually die when the charger port collapses and you get 19V up the centre pin. So you have to replace the charger and the port at the same time. Some Lenovo's have the identification pin going directly to the EC, and this can result in destruction of that too when you have a bad charge port.