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.
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October 1st, 2008 at 9:12 am
I changed the power jack and the new one was fine for a couple of days. but now the computer is turns on for 5 seconds with the fans working and than the fans shuts down and the screen is black
September 27th, 2008 at 4:48 am
Had jack replaced, worked on AC until I put battery in. Shut down with battery and appears to have died. No fan movement, no lights, nothing. Multimeter shows power into mb. Can’t find the other post regarding this same problem, any solutions or ideas of what causes this?
1. Replaced jack
2. Worked on AC Power
3. Put battery in and turned off
4. No signs of life(No fan movement, no leds, nothing.)
Sincerely,
Did the battery short the motherboard.
September 26th, 2008 at 5:41 am
Follow up on #588-589 faulty onboard memory. The RAM got worse over time & began to corrupt files. Laptop became completely unusable, so I decided to try the A60/65 trick by removing the onboard RAM & just using the expansion slot. This does not work for A70/75. You will get the beeping sound just as if you had no memory installed. Seems that both the BIOS & Video card must read from the integrated memory & will not bypass to the expansion slot. Don’t bother to call Toshiba for a replacement, I already did & they want as much for a new motherboard for this model as the cost of a new laptop.
Good Luck….Rich
September 18th, 2008 at 10:07 am
This is in continuation to my last post.
I have a feeling that though the AC adapter is delivering 18V to the MOBO just after the jack, something is wrong in the MOBO, either some capacitor, resistor, etc. This in turn is not supplying the adequate voltage to the MOBO. The voltage that is going to the MOBO is low. Hence the battery charges, but very slowly and hence the Laptop doesn’t turn ON with just the AC Adapter. Basically a case of low voltage. Any comments?
September 16th, 2008 at 1:58 am
I have a toshiba Satellite A35 with the same problem. I replaced the DC jack with an alternative but i power up, it starts then shuts down and keeps starting and shutting down. What could be the possible problem?
September 15th, 2008 at 8:31 pm
CWO2TT,
Could be loose connection somewhere inside the laptop. You can try to assemble and test your motherboard as it shown on the last picture in this post: Laptop is dead. How to troubleshoot the problem.
If it works fine when the laptop is stripped down, start assembling it back together and test after each step.
September 14th, 2008 at 2:40 pm
i took it apart today and the center post loks like it had flux applied but it looks like it was never soldered. I works now.
thanks for maintaining this site. i found it invaluable in taking the laptop apart. i got a white sheet of paper and taped the screws to it with a with a step number next to them. it orked great.
September 13th, 2008 at 9:40 am
I have the same problem as post 607Kokuho. I have not tried to resolder yet .
1) It turns ON for 5 seconds and then turns OFF automatically.
2) The AC Adapter LED is always lit. There is no loose connection. I have wiggled the chord but the LED is always lit.
3) 1st led (power) shows lit, second led is not on, third led is orange showing battery discharging.
if I wrigle the connection sometines the second led goes green.
September 12th, 2008 at 8:15 am
GREAT SITE! Toshiba Satellite M35X-S161. Had exactly the symptoms of bad pwr jack. Attempted repair. Now have all LEDs, battery charges, boots 1 out of about 5 pwr up attempts. When it boots gets as far as user window and then I get the black screen of death. When it starts w/o booting I get about 5-10 sec. fan w/no HD LED.
Have I FRIED/BURNT the MB or is there still hope?
Thanks and have a great American day!
September 11th, 2008 at 12:36 pm
My Laptop runs perfectly with battery.
With just the AC adapter:-
1) It turns ON for 5 seconds and then turns OFF automatically.
2) The AC Adapter LED is always lit. There is no loose connection. I have wiggled the chord but the LED is always lit.
3) The battery charges but very slowly.
I have resoldered the power jack. But the problem still persists. I can see 18 volts with a multimeter inside the MOBO (after the jack). In other words it doesn’t seem like a faulty jack but the symptoms are like one.
If I plug in the AC adapter while its running on battery the LCD brightens up as would happen in perfect conditions, and also shows “battery charging”. But the Laptop still runs as if it is running on battery only, hence after an hour when the battery reaches 0%, it shuts down. Any ideas?