DELL Vostro 1400

[scobie_21]

I have a Dell 1400 that wont power up Im getting a short on pc78 an pq18,and more caps under the processor and when I remove process some are still shorted other are not. Im not experienced on Mb repair.
Any pointers would be great

[momaka]

Re: DELL Vostro 1400

With issues like that, including a picture of the affected area is usually a good idea so that we know what you are looking at.

What makes you believe the problem is in that area and what are the symptoms of the laptop?

[scobie_21]

Re: DELL Vostro 1400

Thanks for the reply. This MB I was told had a bad DC jack upon inspection the jack was found to be OK with 19v to the motherboard.
The board will not power up adn I was just measuring various areas and found quite a few caps short around the processor, when the cpu's removed some are not short anymore but some are. I was hoping somebody had seen something like this before and give me some things to check.

[momaka]

Re: DELL Vostro 1400

Thanks for the reply. This MB I was told had a bad DC jack upon inspection the jack was found to be OK with 19v to the motherboard.

Right, but it's still possible that the charging/power circuit can be faulty.

The board will not power up adn I was just measuring various areas and found quite a few caps short around the processor, when the cpu's removed some are not short anymore but some are.

Those caps likely filter power to the CPU and/or northbridge. They are essentially in parallel with the CPU and northbridge, and CPUs usually have a very low resistance, thus explaining why some of the "shorted" caps were no longer shorted when the CPU was removed. The other "shorted" caps could be in parallel with something else, or there may indeed be one that is faulty, causing all of them to appear as shorted.

Again, it's hard to give advice without knowing what we're looking at. This could be a unique problem or it could also be a standard problem.

[severach]

Re: DELL Vostro 1400

Put your DMM on diode, install the CPU, and test the caps that appeared shorted with the CPU in. If your DMM shows 0.000 then it is not suitable for testing motherboard shorts. If it shows 0.008 or above then it can tell the difference between an actual short and something that is almost a short. North bridges can test at 0.025-0.060.

[scobie_21]

Re: DELL Vostro 1400

I will do that, excellent info thank you .

[ravi_1617]

Re: DELL Vostro 1400

Hi!
Dell vostro 1400 turning on and off 6.5 seconds .off for 1 sec on than again on.
on adapter power only.
on batter turns on and off not on it self.
battery charging fine.
all coils have power according to schematic.
cpu is also heating after long run .
fan not spinning any time