rtankm... Welcome to AA! :wave:

Experienced the same with my pair of F110, fixed at JL, replaced defective worn out caps and before I re-installed the heavy back plates I replaced the large size 5.0 amps fast blow fuse with audio grade to conduct test.
The sub responded to fuse changes, this particular fuse smoothed out the base so much making my eye lids drop.
Kept experimenting until I found what I wanted.

I bought a used f110v1. It had a slight hum when only the power was plugged in. Changing the volume or high pass filter didn’t make any difference.

After using it for a month or so the sub now has a rumble when not plugged in. The rumble gets louder and quieter with the volume knob and even goes quiet when volume is all the way down. Also changing the high pass filter will affect the sound. I’m assuming that somehow the amp is being fed a constant signal somehow. When I connect it to the receiver via rca it won’t play what is coming from the receiver, just the rumble.

I am planning to open it up and replace the capacitors when I get some free time. I think I’m gonna try to replace all the capacitors so I don’t need to order capacitors multiple times.

Does anyone know if it is easy to replace the capacitors at the bottom of OP’s picture with the black tar looking like stuff?

Hi. Im new to this forum and i signed up just for this thread. (they dont sell much of these subs in Norway so not much help to get here).
Ive had a jl fathom 113 for 6 years and last week it died a silent death. No response when i shut it on or off, no lights and no humming noise.
So i did what dan suggested and removed two of the capacitors (33µF 400v and the 100µF 35v). I checked them using a multimeter with capacitance, and it showed 31µF on the former and 87µF on the latter. So i guess its not these capacitors thats defect. Any ideas at whats the cause? All the capacitors looks ok and there are no "burned electronics" smell.

There are no active light diodes on the curcuit board as well, and the main DC in only has 1v when measured. So the fault must be pretty early in the power chain. Will a defect capacitor terminate the current or wil it go through it?

I changed the two capacitors (same as dan), and i got my jl f 113 working again. So i saved at least 500 usd on the repair as jl norway dont have a standard fee. Hopefully my sub will last more than 6 years now that i have installed better capacitors

Way to go...glad things worked out for you! :thumbsup::thumbsup:

Just to be clear, even though they checked out “close enough” with your meter, changing them out fixed the issue?

I have the same problem as Steven84 last year and changed out the caps as suggested by some of our fellow contributors in this forum. It works!

This was how it look like before I replace it, looks good on the outlook.
<a target="_blank" href="http://imageshack.com/f/ponlNV57j"><img src="https://imagizer.imageshack.com/v2/1024x768q90/924/nlNV57.jpg" border="0"></a>

This is the cap removed, and it looks dried out or something and crack open. Not sure if it is due to me when desoldering it.
<a target="_blank" href="http://imageshack.com/f/pnACKwvrj"><img src="https://imagizer.imageshack.com/v2/1024x768q90/923/ACKwvr.jpg" border="0"></a>

Many Thanks
 

Hi All,

Just had to join and offer some heartfelt thanks for the contributions in this thread.

I have two of the original F112s. Both had died within a short period of each other.

Perhaps not a huge concern if you live in the US, but the possibility of even shipping the amp section from Australia for repair/upgrade was a no go.

I did the cap replacement on both, and am pleased to say they are now both back up and running. I had absolutely no experience with this sort of thing, so the sight of those beautiful green lights on the front panel was one to savour.

Thanks again.