Problem with a Macintosh LC

[toples50]

Today I tried to power up my old LC but nothing...No chime no video only the fan works.Also I had some sounds from power supply.Any suggestions?

 

[uniserver]

if you open up the psu you will see there are some caps that are super bad.

the 4 as marked are always completely bad.

Also, There is 3 bigger caps right there, that are not marked, other members on those form suggest to replace them all.

it probably wont break the bank to replace them as well as the other 4  (even if they have no signs of leakage) 

 

[olePigeon]

That'll fix the power supply, but he/she should also recap the motherboard.  I haven't run into an LC that didn't need a recap.

 

[uniserver]

I like when you turn them on and they make varying pitch whine

 

[Juliet Elysa]

uni - like this video?

 

[toples50]

I washed the motherboard but nothing.Only the fan seems to work at the moment.No sound no video.

 

[Ferrix97]

If you have experience with soldering, I have some videos on my YouTube channel that show how to replace capacitors in the PSU and on the Motherboard

 

[toples50]

I found the solution and the Lc finally works!I've used a hair dryer on Power Supply and voila!

 

[Ferrix97]

Great!

but, the solution is only momentary, you need to replace the capacitors inside.

If you continue to heat the PSU, you will reach a point where it will not power on no matter ho much heat you apply on it. You may also risk damaging the Logic Board.

if you need help replacing the capacitors, check out this video

 

[olePigeon]

And if you're going to recap the power supply, you might as well recap the motherboard while you're at it.

 

[uniserver]

haha where did you hear about the hair dryer

pretty nifty trick eh?  lol

re: that Classic II....    That is pretty screwed up!!!!!!!!!!!! HAHAHAH!

 

[Elfen]

I've heard of the hairdryer trick on several places on the net and even seen a demo of it on YouTube, which basically says that the caps in the PSU need to be replaced.

You also need to look at your PSU Connector and check the clips inside and make sure they are not weak or corroded, they look dark, black in a worst case when they are corroded. Corroded pins on the connector forced the PSU to work harder since it has to go through the resistance of the corrosion on the pins. And they are easy to break off the connector when corroded. The connector pins in the plastic harness should look silver and shiny. And corroded one should be replaced.

 

[toples50]

Thanks very much guys!