Gday everyone,
I just finished assembling my new XinTD C8 V5 with a Qlite that I added 4 chips to. I was super careful with adding all the chips and my Fluke DMM with some upgraded leads is measuring ~4.6A at the tailcap which is what I expected with 4x 380mA chips.
Anyway the modes won’t work. I have soldered the 4th star as I wanted moonlight, low, medium, high. But it just stays on high all the time. Is this a faulty driver? or could I have stuffed it up somehow?
Tim
You could have shorted something when you soldered, double check all connections and check the leads going to the star, make sure they haven’t shorted to the reflector
I would check to see if this happens without the reflector installed. I never figured out what exactly was shorting on what, but I recently had a similar issue with a C8 build. Everything worked fine until I tightened the reflector/lens/bezel assembly, putting pressure onto the MCPCB and wires (even with insulation gaskets installed). As I tightened, the light would eventually either turn off completely or run at 100%. I adjusted my soldering technique and redid the positive and negative leads. It's been fine since. I'm still learning. 
We all are 
Ok, I just checked the connections that are accessible without pulling the driver out of the pill and everything looks good. Tried operating it without the reflector in at all to remove any chance of a short there and it made no difference. One other thing though is I did a couple more tweaks to the driver spring and the tailcap switch spring to make sure their resistance was as little as possible. Tested the tailcap reading again and it was pulling about 5.5A!! Is it possible that it has somehow gone into direct drive? Will an XM-L2 even pull that much in DD? I am using a panasonic NCR18650PF cell.
Sounds like the led is going direct to ground, bypassing the driver. I would remove the pill and inspect everything. If you find nothing, then I would remove the driver and inspect connections there.
It would appear that the reflector is shorting against the negative lead on the star causing it to go direct to ground. So I took another tailcap measurement with the reflector out and now it is only pulling 0.55A with still no modes.
Did you ever get resolution to your issue?
I have no idea haha I completely forgot about this thread. I think I might have just thrown the driver away and done another one that worked fine.