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.
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May 20th, 2007 at 4:04 am
I have a HP Pavillion NX9110 that is acting very weird… when i plug the AC I can start the laptop but there are no lights (not even power lights or battery charging lights), but the fact is that the laptop can start, the LCD is black and I can eject the DVD drive… any advice about what is happening?? I was told it could be a DC problem but if I can start the laptop… how come its the ac?? I wonder if the DC was broken in any part, in case, would the laptop receive that power??
May 20th, 2007 at 4:00 am
HELLO YOU ALL, I BUY SECOND HAND LAPTOPS FROM THE US (I’M FROM SPAIN) AND NORMALLY ALL THE LAPTOPS I RECEIVE HAD BAD AC ISSUES… ALL I DO IS TO BUY DC REPLACEMENTS FROM EBAY, JUST WRITE YOUR LAPTOP MODEL BESIDE THE WORD “DC” AND YOU’RE DONE. GOOD LUCK!
May 16th, 2007 at 6:42 pm
Mike Bailey,
If you installed any extra memory, remove it and try starting the laptop just with base memory. If it doesn’t help, remove battery, wireless card, DVD drive, hard drive and try again. If the laptop still will not start, most likely it’s a motherboard related issue. You’ll have to replace the motherboard.
May 14th, 2007 at 12:49 pm
I have a toshiba A75 S206. The other day while it was booting I plugged in the power adapter. A few seconds later everything on the screen was gone. Now if you press the power button or just plug in the AC adapter only you can hear the fan turn on, but no lights come on except the power light on the front (the one furthest to the left to say you on AC power). Thats it. If the motherboards was not getting power why would the fan come on (especially if I haven’t tried to turn the computer on at all)?
May 14th, 2007 at 7:07 am
Thanks for the heads up, but isnt the waranty void after opening the laptop and “tampering” with it? I’m just afraid that toshiba will say they cant help me because I tried to fix it myself.
After reading the first few lines of that PDF, it looks like that is my problem in a nutshell that is being addressed.
thanks
May 13th, 2007 at 11:24 pm
Bret,
I think not in your case. You can hear the fan and hard drive activity, so the motherboard is getting power.
Sometimes you can get a black screen on startup because of a bad memory stick. Did you check the memory?
I believe you have a Satellite M35X notebook, right? Toshiba extended warranty for this model. Contact your Toshiba authorized service center and ask them about this warranty. You might be able to fix it for free.
May 12th, 2007 at 11:17 pm
I posted here about a month ago with a problem of my screen going black after turning the computer on. I wanted to post again with some updates…
I was actually able to FIX the power jack problem using the solution detailed on this webpage. now there is no more flicker and the cord doesnt have to be wiggled to make the battery charge.
However, every time i turn the computer on the screen is completely black, not even lighting up. I can hear the fan and the hard drive rev up for a couple seconds, but those stop shortly after. All power seems to be lost at this point (cant eject CD tray either).
A couple times i was able to get all the way to windows before the screen goes black. the power light on the front remains lit after this however, untill i hold the power button for 5 seconds.
Also, the blue light around the power button NEVER lights up, under any circumstances. This I can live with though…
Above it is stated that if the trace between the top and bottom is damaged, it can cause the mobo to not get power…could this be the case here? and then it says that it can be fixed with a piece of wire being run from top to bottom, can anyone elaborate on that?
I’ve had this thing from my boss for probably over 2 months now, and i would like to give it back without having to send it in with money out of my pocket. ideas?
thanks, bret
May 7th, 2007 at 5:53 am
bp4654,
If you replaced the power adapter and still experiencing the same problem, most likely it’s a motherboard problem. I think you’ll have to replace the motherboard.
May 7th, 2007 at 1:41 am
I have a Toshiba Satellite M65-S809 laptop. I recently experienced an unexpected loss of operation from the laptop. I didn’t see the AC power light on the laptop when the power cord is inserted in laptop. Neither did I hear a low battery sound. If I start the laptop the power button lights up for no more than 3 seconds before dying. I thought it was a power adapter, so I bought another to find out I had the same results. I called Toshiba who suggested I buy a new motherboard….BTW, laptop is only a few months pass the basic warranty period of 1 year. I looked at the power connection which does not appear to be bad. I therefore start to believe it’s a motherboard problem of bad circuitry. To troubleshoot a motherboard is like looking for a needle in the haystack.
Do you believe I’ve exhauted every possible assessment to draw a fair conclusion of a bad motherboard.
Appreciate your advise and/or guidance.
Aloha…BP
May 4th, 2007 at 1:24 pm
Hello,
I have a MX35 and the d/c plug (external) is shot. I need to solder on a new one. Does anybody know what size this plug is and where I could get a replacement? Thanks so much
Matt