My Wurkkos HD20 has been great for the week or so since it arrived, but has just stopped turning on.
Just before it stopped turning on, the UI seemed to behave a little strangely - normally a single click should turn the light on and off, but I seemed to have to hold the button. While playing around with it trying to work out what was going on, it’s now stopped responding entirely.
Here are some things I’ve tried:
Charging the light again - the power button flashes blue
I tried the unlock combo of click-click-click-click-hold per the instructions, in case the light was locked - no change
I tried re-tighening the top and bottom caps several times
I checked that the positive terminal of the battery was facing towards the head
I cleaned the tube contacts with a cotton swab
Another thing: the HD20 will still act as a power bank and charges my phone when connected with a C-to-C cable - the power button lights up amber while connected and for a few seconds after disconnecting.
Once, while fiddling with the button, I was able to get the flood to come on in turbo mode, but was unable to turn it off again or change mode (I had to loosen the tail cap to turn it off). I have not been able to turn it on again since.
good, also clean the contact rings in the head and tailcap
Do not add more lubrication to the threads, as it can migrate and block electrical contact.
I also suggest you use a dry paper towel to wipe off any excess lube on the threads, to prevent lubricant from flowing between the ends of the body tube and the contact rings.
Do use the stock battery, to eliminate the possibility that some other battery may be too long and is preventing the ends from screwing down far enough to make good contact.
Thanks @jon_slider. This is actually already a replacement for the first HD20 I got which seemed to have a similar problem. The first one delivered had inconsistent responses to button presses and then stopped turning on when I initially unboxed it. It also continued to function as a battery bank just like the replacement. Wurkkos were very good about trying to help me with the issue and then sending this replacement.
I guess I was asking here hoping there might be a UI / firmware quirk with a known workaround, rather than a physical problem with the HD20 in general.
I have no direct experience w the HD20… so just a wild guess… maybe the switch retaining ring is loose? (caution, if youre going to try to unscrew and look underneath, be sure to remove the battery first)
I hadn’t noticed the little notches in the retaining ring, but I was able to engage some circlip pliers and get the ring unscrewed. It looks like the ring just holds the seal in place, the circuit board underneath seems held firmly in place.
Directly pressing the switch without the seal in the way, I am able to turn the light on!
Seems I spoke too soon - even without the seal in place, the switch doesn’t seem actuate reliably. Sometimes it doesn’t respond to presses making it hard to turn on or off, let alone access other UI functions
now that you know where the actual switch button is, maybe, just maybe, the failures you were experiencing were due to pressing the edge of the rubber button, instead of the center…
hopefully if you make a point of pressing in the middle of the rubber button, the issues will resolve
I doubt the customer service rep that deals with your email, has any idea about mechanical assembly… at best they could give you a refund or replacement,
suggest you consider asking for a replacement with a different model, if there is an alternative that interests you…
I remember that, a few eons ago, there were some problems with BLF A6 and Tank007 lights. So here are a few other home remedies that might shed a light (!) on the matter.
Is the body tube reversable? if so, reverse the tube to see if that makes a difference. The early BLF A6 lights were VERY cost oriented manufactured. That meant that the threads sometimes missed just that extra micron to make proper contact.
In the AAA Tank007 lights all funny bits were located at the business end (in the head). The body just had a spring to push the battery forward. No more. And that’s where things went wrong. Remove the tailcap and try to connect (shorten) the end of the battery with the bare end of the body. You can use a teaspoon or a pair of scissors. (And maybe an extra set of hands ). Then check with the button if the issue still exists.
That does not surprise me. I like their lights until they malfunction. A total of three different Wurkkos lights including the latest issue with the TS 11…
They work for period of time then the user interface goes wacky. I can’t think of the terminology. But it’s basically like a system reset. I’m twisting the tail cap doing a couple other things and then reprogramming it. I’ve done that twice with this light. Did it three times with the other lights I don’t even use them anymore they just keep screwing up too much. It was fc13.
Hope it works out for you and you get a replacement if you still qualify.
Cleaning the contacts can help. But it hasn’t resolved one issue I’ve had with these lights. It’s a problem with the driver and electrical components I guess that’s the same thing!
And on the other hand I have several in daily use for over a year with no issues.
some people just seen to be unlucky and get all the lemons, which amazes me-- the odds are exponentially against it.
Not saying I dont believe anyone about the issues, its just so weird for getting morevthan one unless bought together; if from same production day it would be more probable.
I have no idea how to help directly, but I wanted to note, unlock is 4 clicks only, not 4 clicks with a hold… wondering if you confused the ui somehow? (Shouldn’t be possible, all lights ive seen ignore extra presses as if they’re not there… but who knows? )
With battery attached with multimeter find the pair of terminals that are under voltage (3V). Then with deattached battery check the resistance between “+” and “-” terminals. When button is pressed the resistance should go to zero.
Bridging those terminals with a paperclip turns on both the lights I have, neither of which respond to button clicks any more.
I also measure a voltage across the terminals with the battery in. However, I don’t see a resistance drop when pressing the button with the battery out.
So I’m fairly convinced the problem is a bad switch in both cases.
