E5500 - not functioning on AC

[spleenharvester]

Re: E5500 - not functioning on AC

Done

It gets weirder. When testing from the outer sleeve of the adapter to DCIN, there's a full 19V. Almost everywhere else - the CPU caps, USB power, the whole lot - reads 13.3V. When taking readings from ground shields etc, this reading is 0v.

Also 19-13.3 gives us the ~5.8V that was showing up everywhere earlier.

:s

[rievax_60]

Re: E5500 - not functioning on AC

Done

It gets weirder. When testing from the outer sleeve of the adapter to DCIN, there's a full 19V. Almost everywhere else - the CPU caps, USB power, the whole lot - reads 13.3V. When taking readings from ground shields etc, this reading is 0v.

Also 19-13.3 gives us the ~5.8V that was showing up everywhere earlier.

:s

That is normal when a ground is open. leave the meter referenced to the plug sleeve. Start taking measurements at the socket's ground pins, gradually moving away from the socket. When you measure anything other than 0v, means that you have gone passed the open circuit fault.

EDIT: second thoughts, that does sound odd.

[rievax_60]

Re: E5500 - not functioning on AC

Or just do continuity tests from the plug sleeve. Less risk of doing extra damage.

[spleenharvester]

Re: E5500 - not functioning on AC

Okay this is getting stranger. Measuring the voltage between the PSU's outer sleeve and the jack's ground sleeve, I get ~0.07v.

If I take a reading between the PSU's outer sleeve and DCIN, I get 19v.

If I take a reading between the jack's ground sleeve and DCIN, I get 14v, which slowly drops to about 11.8v.

If I then measure the voltage between the PSU's outer sleeve and the jack's ground sleeve, I get about 3.1v, which gradually drops back to 0.07v.

All this is happening with the daughterboard only.

So either the sleeve is faulty or a cap somewhere?

[spleenharvester]

Re: E5500 - not functioning on AC

Just had an idea. Is it worth getting some wire, and connecting the ground from the motherboard to the outer sleeve of the PSU barrel, and seeing if it works?

Since it is the ground on the board that reads 13v. Or would this damage it?

[spleenharvester]

Re: E5500 - not functioning on AC

I think the problem is the DC jack. There is no continuity between the adapter sleeve and the jack's sleeve - on my Dell X1 they are connected.

Would it be silly to just bridge the adapter with the ground sleeve to see if it works?

[rievax_60]

Re: E5500 - not functioning on AC

It should be ok if you connect the earth sleeve to the socket pins that you are certain are ground.

[spleenharvester]

Re: E5500 - not functioning on AC

Just did it, I can't get my hands to stay steady enough to see if it POSTs (I have a tremor) but we get lights and power!

So is this deffo the jack then and nothing else? Or is there still possibly a dodgy cap?

Last time I tried to replace one of these silly 8-pin jacks, I resorted to using a heatgun, and the PCB snapped before the jack came off :/

[rievax_60]

Re: E5500 - not functioning on AC

A faulty socket is what everything points too. Maybe you can see the problem with it if you look inside the hole.

[spleenharvester]

Re: E5500 - not functioning on AC

Just tried again, it POSTs!

Guess all I can do now is try a new jack. Given the two grounds don't even seem to be connected on the jack I think that's all it really can be.

Thanks for all your help man, it would still be a doorstop otherwise!

[spleenharvester]

Re: E5500 - not functioning on AC

Eugh.

Replaced the jack today. Worked perfectly for a few boot cycles. Now we're back at exactly the same problem in the first place. Open ground at jack.

I've ordered a brand new daughterboard in the hope that may fix it.

[spleenharvester]

Re: E5500 - not functioning on AC

Replaced the daughterboard entirely and it's been working fine all day so far. Really odd - I fail to see how a daughterboard can kill a jack.