Linksys EF2S24, V2 not working

[shovenose]

once it is plugged in the power/LAN lights all go on, then off, then on, then off, then on, then off, very rapidly. You get the point.
On the connector from the power board to the main PCB, (analog multimeter black probe on black connector, red probe on red connector), it bounces up and down at about 1 volt. No visible bad capacitors. Ideas?

[retiredcaps]

Re: Linksys EF2S24, V2 not working

Pictures of the board would help.

[shovenose]

Re: Linksys EF2S24, V2 not working

I've attached a picture of the power supply.
The secondary caps are Ltec. 2x 2200uF 10V and 2x 1000uf 10V. Even though they look fine, is that the first thing I should do, replace them?
Please look at picture and advise :-)

Oh and there is a slight click, click, click coming from the PSU.

[shovenose]

Re: Linksys EF2S24, V2 not working

Pictures of the board would help.

You posted while I was uploading the picture... it should be working now!

[retiredcaps]

Re: Linksys EF2S24, V2 not working

Oh and there is a slight click, click, click coming from the PSU.

That is the PSU trying to startup.

I would suspect either

1) bad SMPS chip (IC1)
2) bad electrolytic startup cap (the one between IC1 and IC2)

[retiredcaps]

Re: Linksys EF2S24, V2 not working

3) Measure the DC current across that startup cap. Is it steady or fluctuating?

4) What is the part number of IC1?

[shovenose]

Re: Linksys EF2S24, V2 not working

That is the PSU trying to startup.

I would suspect either

1) bad SMPS chip (IC1)
2) bad electrolytic startup cap (the one between IC1 and IC2)

The little Taicon 47uF 25V? Should I try to replace that?

[shovenose]

Re: Linksys EF2S24, V2 not working

Would either of these be suitable for using to replace it? (I don't ahve that exact one):
Hitano 22uf 50v
Fuhjyyu 10uf 50v
nichicon 100uf 16v
Samxon 680uf 16v

Thanks!

[retiredcaps]

Re: Linksys EF2S24, V2 not working

Would either of these be suitable for using to replace it? (I don't ahve that exact one):

1) Did you see post #6?

2) Get the right cap. 47uF 25V is fairly common cap in PSUs (more likely 47uF and 50V).

[shovenose]

Re: Linksys EF2S24, V2 not working

Sorry, I missed Post 6. I will check that cap tomorrow.
I would like to use a cap from my collection. If I ordered online it would be stupid for 1 cap, and if I were to get it local I would have wait until next Saturday. And I'm not patient enough for that.

[retiredcaps]

Re: Linksys EF2S24, V2 not working

Sorry, I missed Post 6. I will check that cap tomorrow.
I would like to use a cap from my collection. If I ordered online it would be stupid for 1 cap, and if I were to get it local I would have wait until next Saturday. And I'm not patient enough for that.

For test purposes, you can take an used cap from a PSU. If it works, then order the proper cap with your next order.

[shovenose]

Re: Linksys EF2S24, V2 not working

That's a pretty good idea... even though knowing me I would never get the right cap (I would leave the test cap in there )

[retiredcaps]

Re: Linksys EF2S24, V2 not working

And I'm not patient enough for that.

Members who live in the USA all report that if you order from digikey, it takes about 2 days using United States Postal Service 1st class mail to arrive. Additionally shipping is around $2.75.

[shovenose]

Re: Linksys EF2S24, V2 not working

Shipping of almost $3 for a single tiny part? loL!

[retiredcaps]

Re: Linksys EF2S24, V2 not working

Shipping of almost $3 for a single tiny part? loL!

Very reasonable when considering the cost of gas and time. However, I do balk at $8 USD shipping to Canada. I generally save up for a big order to ammortize the shipping costs.

Unfortunately, any order over $20 USD gets dinged by Canada Customs for tax, GST, etc.

[shovenose]

Re: Linksys EF2S24, V2 not working

Important new discovery:
I put the power board sideways to get easier access to the measuring of the startup cap. Well, it did the clicking thing a few times then it fired up and STAYED ON...
I plugged in an ehternet cable and it seemed to work!!!
Why? What does this mean?

I'm uploading a video right now, just a sec...
OK you can download the video here:
http://img256.*************/img256/975/ff9.mp4
(I use VLC to play those files)

[mariushm]

Re: Linksys EF2S24, V2 not working

Maybe bad soldering? Inspect the back side of the board especially near the TO220 chips (the ones with three leads) and the bridge rectifier the rectangular thing on the left of the large transformer.

Also, as you mention clicking... that could be from a relay and it just so happens that white rectangular thing in the lower left corner looks like a relay and the two wires going into the socket near it seem to come from the mains.
The relay may be bad or the soldering at the bottom may be bad (could be due to some short that fuse didn't protect it from)

Inspect the back side and report.

[shovenose]

Re: Linksys EF2S24, V2 not working

The soldering looks great. However, when I shake the thing, there is a rattling sound. I think it's coming from that corner. Might that have something to do with it?
By the way, I screwed it back down and now it seems to work. But, it does do the clicking thing once or twice before starting up, about half of the time when I plug it in...

That white rectangular thing is marked CX1. I think it's an X capacitor on the input filtering.

[shovenose]

Re: Linksys EF2S24, V2 not working

Alright new progress: I bend the startup cap a little to the side so I could measure the legs.
Bounces up and down while it flickers on and off. Voltage seems to bounce around near 12V

[shovenose]

Re: Linksys EF2S24, V2 not working

To re-summarize:
The "starup cap" that was mentioned previous does have the voltage bouncing up and down while the power cycles on and off rapidly. Would that suggest that it's something on the primary (before the startup cap?)
I'm still interested in fixing this.
Please help.
Thanks!