Bicycle Mechanics - Nexave Shifter problems

I picked up an older novara bike with shimano nexave shifters. The front was shifting fine through all three rings. I took it out for a short ride, maybe a mile or so. Brought it back in and today I can no longer shift to the outer ring.

I've tried looking up shimano's documents for these things and they seem to categorize them under "lifestyle" components, but they don't have a category in the document section for that and I can't find it anywhere else.

I redid the cable, and checked my limit screws and as far as I can tell they're set up right. If I pull the cable under the down tube it will move the derailer enough to shift to the large ring.

I think it's a shifter problem because once I get into the middle ring and try to shift up (These are tap fire shifters, thumb lever to shift to the larger ring, button to shift down), the trigger doesn't pull any cable until the very end of it's action(which moves the derailer just enough for trimming when shifting from the inner to middle).

So now I'm stuck here clueless as to why the shifter isn't trying to pull any cable, what's amiss?

edit: Forgot to mention the model, these are nexave st-t400 shifters and a nexave derailer that I can't find the number on.

I suspect that it's the shifter too. If you have access to an air compressor I'd give the shifter's innerds a spritz of WD40 to loosen the cobwebs and follow that with a blast of compressed air to blow them out. Oftentimes that will do wonders.

Give them a cleaning.... My experience with Nexave Tapfires in general is the are pretty 'gunky' even out of the box.

I gave that a whirl, seems the catch for the pawls wasn't rotating back to catch the next pawl. I think the wd-40 loosened it up enough and it's working fine now. Thanks.