AC and cigarette lighter

[Mr. Pickles]

My 94 has a weird gremlin. The AC and cig lighter will randomly work, say 80% of the time. The last few days, however, they didn't work at all. Not good with temps in the 40's and 50's and pouring rain (need AC to clear the foggy windows). This has been on-going, and usually a hard smack to the dash right where it sticks out between the gauge cluster and middle air vents does the trick. I pulled the center dash trim around the HVAC and stereo again tonight, but didn't do much other than pull out and move some wires, and it started working again. I know they apparently are on the same fuse, which checks out fine, and I've searched other threads but its usually an issue of them not working at all, not just intermittently like mine. Does anybody know if they are wired in series or something, or where there may be a common wire/plug/ground in the area? I've got the service manual in pdf, but it isn't too clear. I say it must be a loose connection in the vicinity, though I've checked out the plugs to the cig lighter and such, and cleaned and used dielectric grease. I'm thinking something farther inside the dash, but who knows. I haven't spent much time with the AC switch and such, that might happen again tomorrow. Anyways, thoughts?