Astrolux C8 problem : Light flickers when on Max brightness.

I got here a stock Astrolux C8 (XPL-Hi, BLF A6 driver), it appears to operate OK at levels 1-6 (including the strobes modes).

However on the 7th (brightest) level, the light flickers.

(Battery used is fully-charged, high-drain flat-top, which doesn't have any problems with other flashlights.)

What could be the problem here? Is it the driver or the LED? (I'm guessing it's a driver problem).

Check to make sure the driver is tight. I have had a few of my builds that had a poor ground connection between the driver and light body that caused a flicker. If there’s a driver retaining ring, it should be easy to snug it up.

Yeh, was gonna suggest that. I just got a light that was going mental, the rr felt snug, but loosening it and retightening it fixed it right up.

With higher currents, if the connection to ground is iffy, the voltage between driver-ground and case-ground starts increasing, potentially making the driver mental. Crank it down, that voltage-rise decreases, and the driver regains its wits.

Good advice… my C8.2 Kaidomane started flickering in high after about 5 seconds or so. I was like WTF? Thought the driver was on the fritz. But it might still be the driver as it glitched out a few times the last few times I used it. Need to detoxit and tighten things up and see if this fixes things.

I had this same issue with my Thorfire C8, same driver, but sst40. I tightened the switch retaining ring and the driver ring and it fixed itself.

Dirty threads could be another reason, when enough gunk accumulates in there both my C8 and S2+ start to flicker, change modes autonomously and even switch off entirely.

A good cleaning session and decent lubricant might fix the issue.

Yep, clean contacts are important. I use dielectric lube (Super Lube) on my lights. Over time grit amd metal shavings build up and can foul the contact points.

Rats!!! I DID find an extremely loose driver in the C8.2 and got all happy and cranked it down tight :smiley: Then went to turn it on… and it started blinking again— THEN it just died :neutral_face:

Something tells me all the de-oxit’ing I might do here isn’t bringing this one back to life. I’ll pull the driver and look around, but probably time to find an XHP-50.2 (6V) clicky boost driver and since I bought it from KiaDomain, I kinda want to find another source maybe?

Otherwise, it’s been a great light for two years at the back door where it was used 3-4 times a week easy- ran on my guns for a while even, and no recoil problems (back then anyway) :stuck_out_tongue:

I’d ditch the boost driver and go right to a 3 volt setup with a 3 volt xhp50.2 and something like a fet+7135. I don’t know the driver size for the C8.2, but usually 22mm is the normal size. If it tales a 17mm, to my knowledge, only Mountain Electronics ever had a 17mm boost driver for a single li-ion 17mm Boost

Just a short update. I tried unscrewing and tightening the retaining ring on both the tail and head (driver) side.

Now, it has the ‘flickering’ effect when set to the 5th brightness level. But the max brightness level does not flicker anymore.

One other thing I noted, is that I have tested other Astrolux C8 (XPL-Hi, BLF A6 firmware) before, and I recall measuring the tail current to be around 5 Amps when at max brighntess. For this “defective” Astrolux C8, I can only get around 3.5-4.0 Amps at max brightness (with a full-charged high-drain battery).

This would seem either there is a contact resistance problem, or maybe it’s really a driver problem of this specific unit?

Remove as much as possible, clean with IPA all contact points on the driver (both sides if possible), clean the RR and the threads the RR screws into, etc. Then snug it up again.