I am trying to repair a Inspiron 4000, the power connector on the mother board is broken, the plug is soldered to the mother board and has taken with it part of the mother board. I am capable of doing micro-soldering but it seems that this is a multi-layer mother board and I can not figure how to do it properly.
Does it seem that I have to replace the mother board? Where can I get one from and approx price? Is it worth it?
Thank you for using Dell's Community Forum.
I would suggest that you contact us in regards to having this repair done. <ADMIN NOTE: Broken link has been removed from this post by Dell>
In warranty, call Dell. Out of warranty do this:
Getting A 4000 Motherboard With Missing Power Connector To Run:
1. On the bottom at the broken connector location is FL1, a square fuseblock. Ground is located on the corner pad where the silkscreened 4 is.
2. Ground also needs to be jumpered between the missing power connector end of resistor R493. Right next to R493 is pads for the missing C708 part, and the missing power connector end of those pads is also the same end of R493 that needs to be jumpered to ground. The other end ot the wire you use to jumper goes to a pad for missing C706 (to the right of the missing power connector) - the end closer to the 15-pin video connector.
1. On the bottom at the broken connector location is FL1, a square fuseblock. +20VDC goes to the corner pad where the silkscreen 2 is.
2. Now use a long wire and bring +20VDC to the primary battery connector area. Between D51 (just to the right of the touchpad connector) and D55 (just above D51) there is a common trace of copper joining the two cathodes. Scrape off the green paint to expose this pad and solder the +20VDC wire there.
The Board should now power up. It wouldn't until I added jumper 2 under the GROUND heading above. Upgrade to the A23 BIOS using the floppy method.
I used the wallwart type power connector and plug to now power the board. Put the plug on the AC power adapter after cutting off the existing connector as close to the connector as you can. Put the connector in the area the old power connector occupied before it broke off. I hotglued it in place to prevent shorting and for stability. I used these:
http://www.switchcraft.com/products/jack-120.html View 1
http://www.switchcraft.com/products/jack-146.html View 1
Message Edited by johnallg on 07-07-2003 11:29 PM
Just to save you 30 minutes to an hour of hold time, I'll tell you what I was told upon calling Dell customer support. My problem was diagnosed as being "motherboard failure", and Dell's only solution for that is to replace the motherboard... even though the motherboard is perfectly fine, it's the power plug that is the problem. I was also told that my warranty had expired 2 weeks prior to my phone call. (That's the warranty that was marked as beginning the day I placed the order. How many people pick up the phone the minute they have a problem? We all try to figure out what's wrong and troubleshoot a little first instead of just calling and saying "something broke", right?) Anyway, to get a Pentium III, 900 mHz motherboard (which, according to Dell, is the most technologically advanced option available for the Inspiron 4000) would cost about $600. So I could spend $600 to have an out of date Dell with no warranty and a motherboard that is known to randomly fail, or I could spend $800 to purchase a new HP computer that is Pentium 4, 2.3 GHz, 60 Gb HD. My husband's HP laptop is 5 years old, has been around the world with the Army and has been repeatedly dropped out of a backpack onto concrete and hasn't had a problem at all. No "motherboard failure" there. My Dell was never abused in the slightest manner. Just food for thought. Good luck!
Thanks for all the info that you and Stonent have provided here. I have a 4150 with a half cracked off power connector. The bottom board layer broke, it's now superglued back.
The 4150 board is similar enough to the 4000 one that I can see that 20VDC is disconnected from FL1 and I can fix ground too, but I wonder about a couple of things. 1) Why did you have to put the long 20VDC jumper to the primary battery area? The layout is different on the 4150/C640 board, but if I still need to do that, any pointers as to where? 2) I am guessing that the third input from the power cord is earth, as the power plug is grounded. Where would it go? Just hope to avoid having to find a way to get at the inner layers of the board!
thanks for any info or pointers to it!
Guess I'm answering my own posting again - getting better at searching the forums. Stonent wrote (somewhere in the forums :-):
Calebjoon sent me his i4000 board that had the burned up power connector. It had shorted underneath somehow. But after reconnecting it still didn't work. For future reference the pinout is like this:
(Looking at the back of the laptop)
Center pin is the ground. This can connect to any ground point in the laptop.
Right pin is the +20V which goes right to a flat coil looking thing.
Left pin I think must be something like a power good signal on a desktop. It doesn't appear to have any voltage really (it showed a little something on the 200mv scale)
I'm guessing it goes high or low depending on the ac adaptor functioning correctly or not. Most likely this somehow charges the mosfet and lets the power go through. This pin connects to the far top left corner pin on the Docking connector
I have seen 2 4000 boards so far with a broken AC jack and neither of them worked from a C/Port. That isn't to say they are all like that but that has been my experience.
Looking at my board, the 20VDC on the right is correct. The board cracks right around the pins farthest "inside" the board, the the right and left ones. The left pin seems to be connected to a small trace on the top of the board, so that may be ok, it is intact. That trace, or more likely the entire connector, is labeled "JDCIN 1", and the connector pins are labeled so that pin 3 = 20VDC, pin1 = grnd and pin3 = whatever it is.... The right (20V) pin is connected to a large trace on the bottom of the board that is definitely open circuited on my board. The middle pin, is farther out towards the connector itself, and must be soldered to a Via that connects to the middle layer ground plane of the board. The frame of the power connector is also soldered to a broken ground trace on the bottom of the board. Wonder what I can get away with for reconnecting ground, assuming that the plane is plated to the layer that broke off? Would like to attach it to a place with a nice BIG connection to the ground plane!
Speculating on Johnallg's original rewiring instructions, I would guess that the extra ground connection he made to that resistor is what is telling the machine that the "power good" is true, per Stonent's idea cited above.
Hope this helps somebody else! Should be true for all Inspiron 4XXX and Latitude C5xx/C6xx, or any board that breaks that connector.