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 find this article useful, please consider making a donation to the author. Thank you!
December 3rd, 2007 at 10:52 pm
Josh,
If the laptop works fine without the top cover, maybe that’s your problem? Maybe there is nothing wrong with the motherboard itself?
You can try this. Run the laptop without the top cover installed. While the laptop running very gently press on the motherboard in the area of the power jack. Be careful, do not touch open circuits. If the laptop still works fine when the top cover is removed and you are applying pressure on the motherboard, it’s possible there is something wrong with the cover.
Take a closer look at the back side of the top cover, make sure there are no metal parts that can touch the motherboard after the top cover is installed. There could be some kind of grounding issue.
Before you install the top cover back, cover the power jack solder points with electrical tape, just to make sure that there is no connection between the top cover and the power jack solder points.
December 3rd, 2007 at 8:39 pm
Okay, I’ve got an M35X-S149 and the same problem mentioned by many people in the thread, I think first by Peter (104, 106, 107) but also similar to 109, 327, 358, 364, 409.
Had the power jack problem and sent it to Toshiba over the summer. Got it it back and the random-shutoffs began and became more and more frequent. It got to the point that it would do the whole fan turns on for a few secs, hard drive doesn’t spin up, and screen stays black.
I have replaced the motherboard and still have the same problem. I have read the whole thread and tried just about everything. After significant troubleshooting, here’s what I’ve learned. It’s not the memory. It’s not software. It’s not BIOS. It will boot perfectly into windows when both halves of the case are open, specifically over the power jack. If the case is completely closed or the slightest pressure is on the power jack, the screen goes blank and the system is unresponsive even though the blue power ring is still lit.
CJ2600 mentions this in #331 and says the whole mobo needs to be replaced. Probably right, but it think it’s also a situation like Mark describes in 321, where the “repair” done by Toshiba or whoever is shorting itself on the internal ground layers. Regardless, it’s still screwing up as a result of the DC Jack, but in a whole new way. If the DC jack wasn’t epoxied onto the mobo, I’d try the pigtail as a workaround.
I can’t believe Toshiba only had to repair these for a year, especially when their repairs are still causing problems. Customer: lost.
November 28th, 2007 at 9:32 pm
I found a solution for A75-S231 laptop “OVERHEATING” problem. After about one year of use, this laptop started shutting down when overheated. I used a home vacuum cleaner to suck out the dust, but it didn’t work.
I finally took it to one of the major national chain electronic stores to get it disassembled and cleaned up, but they said that they don’t do any maintenance work for laptops. They told me to send it to the manufacturer.
A couple of days later, it just dawned on me that the suction power of a home vacuum cleaner isn’t adequate. So, I took my laptop to the coin operated car wash place. I used a car vac to suck out all the lint and dusts from the two circular shaped fan vents (opposite side of where keyboard is located). I was amazed to see how much stuff was coming out of those two vents. I could feel that the suction power of a car vac was extremely strong, even stronger than that of a shop vac. I also used a car vac to suck everything out of the keyboard as well. I ran a car vac for at least 4 minutes until nothing came out.
Ever since I did that, A75-S231 hasn’t shut down due to overheating, not even once. When I place my hand behind the heat sink vent area, I could feel that the hot air was blowing out. Before, I didn’t feel the hot air blowing out. Hope this is helpful.
November 25th, 2007 at 1:23 pm
In the process of dismantling laptop, I lost what appears to be ferrite for antenna cables. Does anyone know what ferrite is used and where can I find it.
November 24th, 2007 at 8:22 am
Thanks! I was guessing that, because the left (power cord) light comes on reliably whenever I plug the cord into the jack, that the jack is OK. And that the problem must be somewhere deeper than the jack. Is there a power module inside that might be weakened and might be causing the symptom of the right hand (battery) light to often fail to come on? And the screen to dim? I’ve also recently added an external USB-powered hard drive. So I am suspicious I might have overwhelmed something. Thanks!
November 24th, 2007 at 12:52 am
Dellywhere ,
I think this problem still could be related to the power jack. Resoldering the power jack should help.
That’s normal. The screen gets dim because you have different settings for LCD brightness when the laptop runs on the battery power.
November 23rd, 2007 at 5:31 am
My A75 charge problem a little different. Left green power light on all the time OK. Battery light on right comes on and off. When battery light goes out, screen dims and battery discharges. Must plug adapter in and out to get battery light to come on again. Is this a solder problem? Ideas? Thanks!!
November 16th, 2007 at 7:58 pm
I have a question…. I currently own a Satellite 2435 series, and I have been having all the above described problems. Not being sure if it was the power jack or the adapter I went and purchased a new battery charger/ adpater. It is now receiving a charge and no flickering, just wondering if this is a temporary fix? The original battery charger/ adapter does not send any charge to the laptop. any info would be greatly appreciated.
November 11th, 2007 at 6:13 pm
I found the N-size power jack that is available at local Radio Shack’s for about $3 makes a great replacement. This jack mounts into the original power connector hole in the case. Instead of soldering to the board, I have scraped of solder mask near the positive connector, soldered solid-core wire to the board and jack, and mounted in this hole. This eliminates the stress on the jack and motherboard by allowing it to flex independently.
November 10th, 2007 at 2:33 am
I got a A75-s231 off of a friend. he said it was mine if i can fix the jaxk problem. it happened before, and it was replaced, and then the jack problem happened all over again, The machine would notice the power, then it wouldn’t and you have to keep messing wtih the cable to get the machine to run on direct power. i resoldered the jack, and put the thing back together and the pwr led, and batt led were flickering between each other no start. i unsoldered and resoldered the jack back on, and now it just flickers once when i hit power button. this off course is the board sitting out naked, and grounded on an antistatic foam pad.
i tried the old jack for the hell of it. the one that was originally replaced by the one i took off the unit. and same thing, power and batt led flickers once. i did the external wiring idea from teh link provided, and still wehn i tap the power button i get pwr and batt leds flickering once. now do i have two bad jacks or is it the trace being broken? i noticed that the solder made it through the holes on the positive and the negative solder points. is the flicker a good thing, and it’s just a bad jack? i don’t know what to think. i’m getting power. i mean the flicker even onces says i’m getting power right? so waht is going on? should i worry about this trace or worry about the jacks being bad? i have no meter to check them.