S Plus - 3100 Code Won't Clear?

[OakTheDog]

* Well, this fixed itself when I moved the machine.  Didn't change a thing, but can't delete the post * 

Hello!  I'm fixing my friend's RW&B S+ machine, and the 3100 code won't clear - I've tried / verified the following:


* Replaced door optics - I get 13 1 when closed, 13 0 when open.
* Cleaned hopper motor and pawl assemblies to ensure works properly / is clean
* Tightened all connectors on hopper male / female ends to ensure works properly
* Checked battery on CPU board for proper voltage, no leaking on board
* Checked all connections to ensure no "wiggle"
* Hopper properly dispenses 10 coins on test mode, no missed coins
* No bill validator in place, coin validator doesn't give "green light" (expected, though)
* Candle lit on both white / blue on top of box
* Reels don't spin up when powering on device - just getting lit candle and 3100 error flashing


Any other ideas as to where I can / should test or check?  I've read the threads, and am running out of ideas...


Thanks in advance!