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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February 24th, 2006 at 3:23 pm
Hey Mike,
Unfortunately, you do not a lot of options. If this laptop is still under Toshiba warranty, take it to a Toshiba Authorized Repair Center. If it is not under warranty, buy a new DC-IN jack and take the laptop to a professional repair shop to re-solder the jack. If they do a good job and re-solder it properly, it should last for a long time. You just have to be very careful with the power plug.
February 24th, 2006 at 3:03 pm
I’ve had an A70 laptop for about a year and a half now and this problem has happened at least 4 times to me. Is there any possible way to make sure it doesn’t break every few months or am I stuck with a bunch of spare parts to sell and get a customized desktop?
February 20th, 2006 at 1:04 am
Hi Kevin,
Most likely the service center did not fix the DC jack and replaced the entire system board. Toshiba apply black epoxy around the base of the DC jack to strengthen the DC jack after they replace or resolder it. I have seen a lot of system board failing because of the DC jack even after it was repaired. In your case I would check the memory module first because the problem you described might occur because a bad memory. You can check it with Memtest 86+ test
February 19th, 2006 at 9:48 pm
A took apart my wifes A75-S209 in an effort to fix what i believed was a bad DC jack. I check conninity and all three pins that as on the board get power from the O.d. ring and not the center post is this correct or is the Dc jack defective.
February 19th, 2006 at 8:46 am
My m35x had the jack repaired/replaced? by an authorized service before the initial warranty was up. after 3-4 months stared to exhibit sudden shutoff, would not restart…no HD activity. Power button would turn on, but system never went any further…no video, no HD…Opened up the unit and noticed that part of the repair consist of a black epoxy around the base of the jack, covering the solder points and components within 1/8 to /14 inch of the jack. Noticed what looks like severe corrosion between the jack and the CPU cooling fan plug.I’m thinking the adhesive they used caused a breakdown of some component and caused my present problem. The job they did looks “neat”, neaning as professional as gluing something can be. Must have been a service tip for a long lasting repair. Now I’m faced with a replacement of the main board at my expense, and I can’t prove what caused the problem. Any way I can post some pics or send you some?
Thanks,
Kevin
February 17th, 2006 at 11:58 am
Wahl Clipper Company makes a very nice portable soldering iron that comes in several models. You can get some very small tips for them in conical or flat styles. I have seen them for sale on the MCM Electronics and Mouser Web sites. Wahl has them on thier site as well but I do not recall if you can purchase directly from them. The product itsel is called Isotip and is reasonably priced in my opinion. I have the DC in jack problem on my Sattelite P15 but see no dissasembly instructions for it. Looks like the P30 might be close enough to get the job done. It is not bad enough yet to warrant tearing it apart but I know I will have to do it eventually. I’m thinking that the input jack should be available from an electronics parts distributor like Mouser but I have not looked into it yet.
Good Luck.
February 17th, 2006 at 10:19 am
Looks like it must be the top part that has pulled away from the board. The connector still can be locked to the tape cable, but the connector itself has pulled away from the board at one end so that the connector pins appear detached from the board.
This is what I’m trying to correct, and why I was hoping I could somehow solder the pins back. From what you said, it does not sound too hopefull for me, but since I have nothing to lose, I would like to at least try to re-attach the connector – I just don’t know if there is any way to get contact between the tiny pins and the board now that they have come loose.
Thanks again for all the help.
February 16th, 2006 at 10:26 pm
The keyboard cable is not soldered to the system board. It’s connected to the system board via the keyboard connector. The keyboard connector on the system board has two parts. One part (top) is connected to the system board permanently and second part (bottom) is a moving part and works as a connector lock. If I understand right, in your case the bottom part is broken.
It’s hard to give a good advice because I cannot see how bad the damage is but you can try next. Insert the keyboard cable inside the connector on the system board as far as you can. After that put the broken bottom part under the keyboard cable and move it toward the top part, trying to lock it. The keyboard cable should get jammed between the top and bottom parts and it should be enough to make a good connection. After that put some sticky tape over the connector.
February 16th, 2006 at 6:49 pm
Turns out the power adapter was bad. Good news: the heatsink is now clean and won’t overheat anymore. Bad news: I detached part of the keyboard socket from the main board while trying to release the locks on it.
The pins are tiny, and don’t appear to be soldered to the board on the back, but must have been mounted at the factory or something. At this point, the left 1/4 of the keyboard seems to work, but the rest of it does not.
Is there any chance I can solder these pins back on? Is there a really tiny-point soldering iron available? The way I look at it, I may as well give it a shot. The keyboard is useless now anyway, so if I mess it up I would either use an external keyboard or just use it as a DVD player.
I know this question is off topic by now, but I don’t know where else to post it. Thanks so much for all the help.
February 10th, 2006 at 4:01 pm
Try to minimize the system. Leave just the system board, the DC jack harness and connect it to the AC adapter. The power LED should light, that means the system board is getting power. If there is not power LED light, than either DC jack, AC adapter or the system board itself is bad.