Replace the dead Electrolytic Capacitors.
IMPORTANT:: YOU MUST DO THIS BEFORE THE REPAIR. Discharge the main supply caps. I use a 560ohm 5W ceramic resistor. see pic 3 below. It is big and insulated and easy to grab (the insulated part that is). In the kit I send a 300ohm with insulated leads. I have found 187v after the TC was off for 2weeks or even more. Just turned off the caps will be charged to 350v, enough power in them to hurt you. Maybe even lethal...... but don't be the first to find out.
Click each picture to expand it and see the details .. they are high res. but fairly small so should load pretty fast.
1. Open wrappers 2. Open the join. 3. Discharge the caps.. ASAP 4. Fully remove the plastic 5. Carefully cut off the goop.
6. Bad 1500uF 7. All 4 caps removed. 8. Close-up caps gone 9. 470uf-16v 470uf-6.3v 1500ufx2 10. Clean out the holes. Map pin**
The cap that was probably causing the failure was the 470uf 16v tucked into the angle of the heatsink. It also looks fine.. it was very high ESR.
Don't be fooled by looks.. the only one that doesn't generally need replacement is the 12v supply which is left on the board.
The list of caps is
1x 470uf 16v (8x12mm) Must be replaced with same voltage. This supplies 12v to the controller chip.
1x 470uf 6.3v (In the kit I usually supply another 16v cap. but this only needs 6.3v. size is important 8x12mm at most)
2x 1500uf 6.3v (10v would be better but they need to be 8x20mm, very high grade and high ripple type)
They need to be high grade caps.. low ESR 105C. Buy best brands, from reputable dealers.. ebay has huge number of fakes. I have a draw full of fakes.. what they send you is not what is in the pictures.
You can also use solid type caps of correct size and rating.
Once finished you can recover the foil shield and use that to wrap around the supply.. it is RF and may have some safety factor.
Note in picture 14..and 15.. I slide a couple of offcuts of the plastic into the high voltage side to double insulate that area. With another small dab of silicon.
As soon as I finish I test for shorts with a meter.. and carefully inspect all solder joins. Use magnifying glass or something high power to see carefully.
Then immediately place in the TC to test. I haven't had a failure yet at turn on.. but you can leave it on power for a few hours to heat up the supply and set the silicon.
If you run into trouble you can peel it open and immediately wipe off the silicon. Remember this is plugged into mains.. don't touch whilst powered and remember every time you power on.. you will need to discharge the caps to safely work on the unit.
I said use silicon putty as glue.. let me clarify that.. because I bought a tube of cheaper stuff and it is ok except it seems to have too much acid in it and eats the copper.
The good grade putty is fine.. you should really buy electrical silicon.. but that costs a mint.
So let me just suggest you test a dab on a bit of copper wire to see if it starts to go green, don't use it. Never had this happen with higher grade Dow Corning stuff.. or even Aldi ones.. just the own brand hardware store.
Don't get it for this job at least.. fine for non-metallic I guess. Roof and Gutter type should be fine. Clear or white.. but I have occasionally bought grey as well.
Good job if everything now runs as it should... but how long before the disk dies or the power supply needs recapping again... all because the initial cause of the problem hasn't been fixed. It runs too hot... and the fan never works to assist.
See fan mod. Apple Time Capsule Fan mod
Or follow the type1 or type3 repair and use an external power supply, Apple Time Capsule Repair
If you are in Australia I am offering a repair service as well as freely offering all this info to help other users.
Just click on above link and go to the Repair Service, and send me an email.
I can also send you a bunch of the right capacitors cheap by post. It is not easy to get them in small quantities.
If you want a set of capacitors and the pre-printed films.. you still have to cut them out.. email me.
That is also paypal account.. so you can pay directly into it.. $11 in Australia.
And finally let me restate the warning
WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING --
The power supply has a pair of electrolytic capacitors on the live side... ie the pair of 39uF 400v. Do not touch any part of the power supply without discharging them.
This is live.. and you need to use the insulation properly.
This is the result..
Here is the cause. The person soldered the 5v supply capacitors in the wrong way around.
Electrolytic capacitors are polarised.. they have a light colored stripe down one side to show -ve.
The board has a stripe that is black to show it is negative. In this case it is narrow.. but clear.
The photo is hard to see but he soldered in the cap with the light stripe nearest to the transformer. (Yellow taped component)
(He also did not replace all 4 caps which is required).
At turn on, the TC supply lasted about 2min.. then blew up. One capacitor burst as you can see from the end.
And also burned out the primary.. although i cannot figure out that connection. This power supply is destroyed.
Double and triple check your work.. Polarised components must go in the right way around.
Note how this can be tricky.. I removed the primary caps so you can see the black stripes on the board are together.
That means the primary caps are mirrored to each other.. and even I at first blithely soldered in with both as per the left side.. as most layout is done.
But I always always double check and saw my mistake. Made suitable noises at the stupid designers who put caps on the board mirrored instead of all the same way.