dEAd DD-3 Delay (IC?)

[aChorusofJays]

My bandmates Boss DD-3 quit on him, and I took it home to check it out, see if I could diagnose it. I don't have a signal generator at the moment, but I have a friend that has one. Let me give some details, maybe you could give me an idea of how to proceed. I don't see any bad solder joints etc...

This is what it does when plugged into 9v Adapter (or battery).
Guitar to Input, 'wet' Output to Amp:
No sound in bypass, *stomp*, LED comes on, still no sound.

Guitar to Input, 'dry' Output to Amp:
Sounds fine.

Again, the wiring and soldering all looks sturdy. I did have someone mention the IC may have died, but I can't find a schematic etc... to find out what the chip might be.

This is one of the latest DD-3's by the way, mostly SMT components.

I would really appreciate any help you guys can offer!

[Processaurus]

Here's a dd-2 schematic, the dd-3 version 3 is very similar (haven't been able to find a dd-3 schematic, $35 from boss, gouge!)http://www.freeinfosociety.com/electronics/schemview.php?id=126

All the part numbers will be different.  Also "direct out" on the schematic is the dry out. It is actually a lucky sign that the wet output has no sound in bypass, because that means the actual delay circuit is probably still good.  Follow your signal (it's nice to have a scope, but you could use an audio probe or multi meter on the most sensitive AC setting) through the dry signal path, after (using the dd-2 schematic's part #'s) the discrete buffers Q1 and Q2, because they are working (we know that because the dry output works).  Check for audio output at opamp IC 1b and 1a, that's your dry signal path to the wet/mono output jack. 

Actually, for starters, check the wiring to the wet/mono jack?