Dell Latitude D600 dead. DC jack issue?

I've been trying to repair a dead Latitude D600.
The unit does not power ON using the AC adapter, no LED lights. I tried using a different working AC adapter from a 600m and didn't work either.
Then I installed a charged battery pack from the 600m into the D600 bay and it power on just fine.

I googled the issue and one suggestion is that the DC power jack could be toast, so I bought a new one over at DCpowerjacks.net
I have it replace by a professional, and after I reassembled the machine the problem persists.

I don't know what else to do, I'm not so incline to do electronics troubleshooting.

What could be going on with this machine, it seems these models had a variety of problems regarding the motherboard and the machine not able to power on because of some kind of weak contact point between the daughtercard connecting to the motherboard when you press the Power Button.

 

Another possible problem is the power board that is between the jack and computer's electronics. It seems to be working OK with a charged battery but unable to handle a DC input.

John

 

I don't get your reply John, please elaborate, by power board do you mean the daughterboard where the power button makes contact that supposedly powers ON the laptop? I don't see why it could not handle the power from the adapter, but who knows.

 

I haven't studied the parts manual, but I would expect there to be some electronics between the DC jack and the rest of the notebook which, as a minimum, would convert the 19V DC into something lower for (i) charging the battery and (ii) use by the main board.

John

 

Well, the DC jack connect directly to the motherboard, there's no individual piece. And is very weird because there's no leds turning on when the AC adapter is connected, checked again after the 'surgery' with a charged battery and yes, still it boots up just fine, but not with the damn AC.

 

I have a D600 that I bought used on E-Bay a couple of months ago and I just love it even though I have a D820 also. I was curious about the power problem as I have seen replacement jacks all over the internet for these notebooks. From what I can see, it is either a bad replacement jack or a faulty motherboard. Looking at the service manual, I do not see another seperate part that can be replaced. I did not take mine apart, but I am wondering if there is a way to test continuity between the motherboard and the socket for the adapter? I can picture a bad solder joint or a bad jack.

 

Interesting chevy05, I'm don't know how to test continuity, a friend of mine recommended me a local electronic repair shop that could help me deal with this issue, but the fact is that the laptop is not mine, and I've already spent some money buying the jack and then having someone resolder the new jack. It could be that the job is not well done, so I'd try again with the local shop if they don't charge too much. I will keep updated here.