1999 accord LX. First ac light on/off would occasionally work or work then stop working down the road. Then (year or so of this) the lights started with a faint blinking and ac would not come on (compressor would not kick in). Finally, everything stopped working. Went to threads and saw the "jumper" around the voltage regulator but also just replace the ac contoller. Found a nice / used on on ebay for $85 (july 2020) and plugged it in. Bummer, nothing worked on this one either. So, went to this thread for jumping the board and son of a gun, worked beautifully. Can't believe someone figured out this fix, but it works!
Don't bother looking at the 'condenser fan' relay. That ain't it. Of course, check the 7.5A fuse on the driver side, but most likely it's just this dang control board jumper.
What a fantastic DIY
I think I figured out how to fix it. I have a 2001 Honda Accord LX V6 3.0 and the AC control lights all went out, could not switch the vent modes, could not activate the AC, but the fan control knob worked fine and controlled the fan fine. the lights came on intermittently and I was able to use AC for a few minutes and it would go out during a drive. it seemed like a battery was dying so I ripped out the center dashboard and remove the circuit board for the AC controls. there are 5 capacitors on mine , I replaced them all and it seems to work fine now. one capacitor I replaced matched the capacitance and voltage but was half the size, I'm guessing it is a low ESR capacitor. I replaced it with the next voltage up which was closer to the size of the old cap, all the others I had no problem. the original caps are japanese nichicon, which is one of the top brands. I tried to do the jumper mod which didn't work at all. so if you lose lights and controls for the AC buttons try replacing all the caps, preferably with nichicon
update- the ac controls light up continuously and I'm able to use the AC compressor normally so I think this did it. the jumper wire did not work for me and at least 1 other person, I think the reason is that our capacitors are partially working. replacing all the capacitors should be the first thing anyone tries because the reason these circuits fail is because capacitors are recommended to be replaced every 10 years. especially if its not being used for a long time, they have electrolyte in them just like a battery. I believe what the jumper wire mod is doing is bypassing the capacitors and tapping straight to an available source of power. that's probably why some of you have glitches like flickering lights or lights that won't turn off. please try this fix first, get someone who knows how to select capacitors if you need help