I took two tries to get it to work too. I think the issue is the metal end contacts are slightly higher than the central (ceramic?) portion. You need set the graphite into those tiny corners [_] to make a complete path from one metal end to the other. It's not hard, just angle the pencil both ways to reach into those corners. 
The pencil trace worked on my Paisen U2 Z6..... now starts in High after light is turned off for more than 3 seconds.... great!!!
much easier than soldering!
5 seconds for pencil line vs 1 hour for soldering (I found that I am horrible with tiny tiny components).
I’m very, very happy with the ease of these results.
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Curious, would anything bad come from pencil lines on all of the capacitors rather than just the control cap?
Not a good thing at least, if the capacitor is not intended to have an alternate discharge path.
For example, normal boost driver needs at least one cap to build up and discharge boosted current. If you add a trace across, the capacitor simply takes longer to charge, the energy is wasted through the pencil trace.
Just wanted to update:
I´ve covered like the whole resistor with pencil marks and now it starts always on high- that´s my favourite UI!
I ordered a cheap 502 with the typical 5 modes and I wonder if it is possible to change it to 1 mode only with this method? Having it starting always on high would be fine, but maybe high only would suit my needs for this light better. Does the pencil trick work or does it make more sense to get a cheap 1-mode driver?
Pretty much all generic drivers can be mod’ded with this pencil trick. Though if you really want one mode, it’s much more efficient to pull the capacitor out instead of creating an electrical short across.
You don't have to solder, you're just pulling a logic level low. Use a pencil here also, much easier to try out options and make modifications should you change your mind down the road, no de-soldering, just erase. 
I used this on a q-lite to get 4 modes (4th star).
Pencil mark is a lot easier, cheaper, and much more compact.
The word 'Budget' comes to mind. 
Really not the $1.10, the pencil only takes 10-15 seconds and takes virtually no room. It won't bump against the cell or extend past the edge of the driver causing fitment problems. It's simple and just works. Are you changing mode groups 6 or 8 times a day?
Just did the pencil lead trick on my sk98. Always loved this light but hated the next mode memory. Now it always comes on in high. Thanks guys.
This didn’t work for me (with the pencil), but popping off that little resistor with a knife made the light a nice and handy one-mode with the UltraOK tactical (no heat issues and it’s not well-driven, so it might as well be one mode). Now, it’s always on high with 600-ish lumens.
I have encountered this problem, but turned out it was just some flux residue on top of the cap. That made the pencil trace non-contact. I cleaned the cap top with methyl spirit and it worked as it should.
And just to update. One of my earlier pencil trace mod lost its memory reset after a few months. This is the one I did without dabbing glue. So my suspicion seem to have merit, that the carbon trace/powder can slowly get knocked off in time if placed by itself.
BTW I used cheap 2B pencil. Pretty sure this result will vary depending on the pencil’s graphite/clay/filler formula.
It’s no big deal though, as modding back is easy. Just thought you guys should know.
I have a 2 x 18650 light with the dreaded next mode function. The tip of using a pencil seems really sweet so I’d like to try it. The only problem for me is that my driver has two of these capacitors. Do I draw on them both, or only one? If one, which one?
Here is a photo of the driver. Capacitors can be seen on right side (3 o’clock) and just left to the very bottom (6 o’clock):
try looking for traces that connects the capacitor to the MCU, i think it could be the one to the right. i guess the one at the bottom could be associated with the coil in boosting or bucking the voltage from the battery
BRILLIANT!!!
I have a SH98 from FT, did the pencil on the capacitor on the driver (used a mechanical and scrubbed from solder to solder on the cap about 4x times [nice heavy line]), went from a 10 second (repeated about 5x times to be sure) down to a good 5 second reset (repeated just to be sure)...AWESOME!
I can’t see any better by looking at the driver rather than this photo, the camera has better eyes than I do 
I’ll try the one to the right and see what happens.
This didn’t work for me…on two different lights. I still don’t know why.
I did it on my Paiesen and it is now down to one mode ,Hi. I am ok with that since the heat management on this thing is fairly good.
Sounds like you made the line too heavy, reset time is less than your half-click duration. Try a very quick tap on the switch, if it changes mode you might want to erase and redraw a little lighter.
Some capacitors have the metal contacts on the ends slightly larger than the dimensions of the body. If the pencil has a rounded point it may not get all the way into that right angle where the contact meets the body, leaving a gap in the graphite. You might need to press harder or sharpen the pencil.