A bad connection between DC-IN power jack on the system board and the system board is a very common problem with Toshiba Satellite M35X and Toshiba Satellite A70/A75 notebooks. If your laptop is out of warranty, then you can fix the problem by resoldering DC-IN jack on the system board. If it’s still under warranty, it would be fixed at no charge to you.
Problem symptoms:
- Laptop randomly shuts down without any warning.
- Power LED and battery charge LED start flickering when you wiggle the power cord or the AC adapter tip on the back or your laptop.
- The battery will not get charged.
- When you plug AC adapter, the laptop appears to be dead and there is no LED activity at all (DC-IN jack on the system board is broken).
To fix the problem, you have to take your laptop apart, remove the system board to resoleder or replace the DC-IN jack. Toshiba Satellite M35X and Toshiba Satellite A70/A75 disassembly guides will help you to remove the system board. Take a closer look at the power jack on the system board with a magnifying glass. In most cases you get the power problem because of a bad connection between the DC jack and the system board, you’ll see a crack between the DC jack connector and the system board.
Here is an example of Toshiba Satellite M35X power jack. The crack occurs between the DC jack pin and the system board.
In some cases the connection is good, but the DC jack is bad itself. You can find a new DC jack for Toshiba Satellite M35X and Toshiba Satellite A70/A75 laptops here. Search for DC jack M35X or DC jack A75.
How to resolder laptop power jack yourself.
UPDATE:
Sometimes, after you replace the jack, you can see that the system board doesn’t get power at all. The battery will not charge and the power LED will not light when you plug in the AC adapter. So, here’s a possible explanation.
When a connection between the positive pin and the motherboard breaks (cracks), the power jack gets loose. You can feel it when you plug in the adapter plug. A loose power jack can damage the trace inside the hole in the system board. Take a look at the picture.
As you see, the positive pin goes through the hole in the system board and you solder it on the top side. Right? What if the trace between the top side and the bottom side is broken somewhere inside the hole? I’ve seen it before a few times. In this case everything looks nice and clean on the top side. When you plug in the AC adapter, you get normal voltage readings between “+” and “-“ pins on the top side, but the power DOESN’T go to the motherboard at all, because there is no connection between the top and bottom sides. Test with a multimeter if there is a connection between the top and the bottom.
If the trace inside the hole is broken you still can fix it. You can run a wire to connect the top and the bottom sides. Be careful not to short something on the board.
Update:
Here’s another solution to fix the power jack problem, it shows how to relocate the power jack outside the laptop base. Check it out here: Toshiba Satellite A75 failed power jack workaround.
When you repair a loose power jack, it’s a good idea to check the jack on both sides of the motherboard. When you remove the top cover from a Toshiba Satellite A70/A75 laptop you can see only points where the jack is soldered to the motherboard as it shown on the second picture in this post, but you cannot see the jack itself as it shown on the first picture.
Removing the motherboard from Satellite A70/A75 laptop is a good idea because the jack itself might has a broken “+” pin, as it shown on the picture below. If the “+” broke off the base, you’ll have to replace the jack.
UPDATE:
Today I received another well written and well documented guide about fixing Toshiba Satellite M35X power connector issue. This guide was submitted by Stephen Macuch. Thank you Stephen for great pictures and detailed instructions.
If you are tired of fixing your laptop and want to sell it for parts you can do it here:
Any Notebook Part – free classifieds. Only laptop stuff.
If you find this article useful, please consider making a donation to the author. Thank you!
October 20th, 2006 at 12:23 pm
Mike,
Looks like a dead motherboard to me. Man, you’ve done everything right to troubleshoot the laptop and it’s as far as you can go. You’ll have to replace the board.
Could it be a bad CPU? Yes, it’s possible but from my experience CPU failures are rare.
BTW, if you removed the CPU for some reason make sure it’s seated properly and the CPU socket is locked.
You can check the warranty status on the Toshiba warranty and services information website. If you are lucky, the laptop is still under warranty.
October 20th, 2006 at 11:52 am
when the A/C adaptor is removed the unit goes dead, no lights no activity, the unit functions normally when using the wall jack, but refuses to accept power from the battery(I tested the battery and it is indeed good)
October 20th, 2006 at 9:45 am
I’m trying to fix our A75 s209, it is basically brand new, we got it about a year ago, and my boss took it out on a trip a couple of weeks after we got it and it “died”
it behaves as follows, power on, fans spin screen does not come up and a second later fnas shut off and power button remains on. I have completely disasembled the unit, same thing, only thing left on the board is the fans and cpu. when I hook up an external monitor, the led on the monitor changes to green for a second after i turn on the power, but then goes back to orange. I measured the power on the motherboard and it is at 19 volts. I am stumped.
October 20th, 2006 at 9:08 am
Manbehindthemadness,
What do you mean by this?
The laptop shuts down when you unplug the AC adapter or the power icon in the lower right corner still shows the AC power source?
Does the laptop start just from the battery, when the AC power is unplugged?
If you think that it’s a hardware issue, have you tried to update/re-flash the BIOS?
October 19th, 2006 at 10:13 am
I have a Toshiba M30x laptop that will power up from A/C just fine, it will charge the Battery fine as well, but it will not switch to battery power when the A/C power is removed, it has recently had a D/C input jack replacement, is there a reed or power diode I am missing? I have checked the board mounted fuses and they all check out.
October 12th, 2006 at 2:20 am
Hello,
I have a Winbook J1 that need to have the power jack replaced. Can you please send me a link showing me how to open up the laptop and replace this part.
Thank You Kindly,
Melinda
PS Do you know where I can buy the power jack(asumming it is not attach to the MoBo)?
October 11th, 2006 at 3:26 pm
Victor,
To connect a regular ATA laptop hard drive to a desktop computer you still need an adapter. If you have a SATA drive, you can connect to a desktop without adapter using SATA cables.
October 11th, 2006 at 3:08 pm
CJ, thanks for the advice. I thought of that today while looking through an ad for a local computer store. I also though of installing the HD right into my desktop. That should also do the trick.
October 11th, 2006 at 2:37 pm
[...] My Toshiba Satellite A70 started having power problems several weeks ago. Although the power cord was plugged in, the computer was not charging and was draining the battery. The little ‘plugged-in’ LED would come up but the battery status LED would still show power coming from the battery. I could jiggle the power cord and it would come back up so I ignored it and got used to jiggling. Unfortunately, the power got more and more touchy and I spent more and more time jiggling the stupid power cord. I first guessed it must be something with my power adaptor but (after cutting open the outer wrap of the cord), I finally put it together that the ‘plugged-in’ LED was coming on but not the battery charging light. This seemed pretty odd. So I finally went out and bought a multimeter. For $20 it was a really good investment and I wish I would have bought one several hours of jiggling frustration earlier. Anyway after the multimeter showed the cord was giving the appropriate 19V without any interuptions, I finally got the bright idea to google the problem and found out that this is a common problem for the A70. Although I have soldered maybe once in my life, the repair didn’t look all that difficult so I thought I’d give it a shot. I ran out and grabbed a crappy Radio Shack iron for $15 and a pack of resistors and circuit board to practice on for $10. You could skip the practice if you were already confident in soldering. [...]
October 11th, 2006 at 12:18 pm
Rusttype,
I don’t think it’s a bad power supply (AC adapter) because when it fails, usually the power button and LEDs will not light up.
It could be a memory failure. Try reseating the memory module/modules. Remove the module from the slot and insert it back. If you have 2 memory modules, remove them one by one. Test the laptop after each remove memory stick.