Hi all,
Long time lurker but first post here - I’ve got a Nitecore EA41 with its original CREE XM-L in it that has gone dim. Fully charged batteries, I get the LED powering on to a very dim state (sub moonlight), mode button swaps it to dim flashing, and the blue LED around power switch just flashes 3 times at me repeatedly as if it is in a low battery state. Managed to get the thing dismantled (bit of a mission - found some instructions for an EA4 on CPF) to get at the driver and MCPCB.
Measuring the LED terminals shows ~5V going at the diode from the driver (which seems odd to me as I thought these were ~3V LEDs), and applying 5V directly to the solder wicking up the two sides of the driver on MCPCB (still soldered to driver circuit at this point) lights it up but only dimly. I can’t see any brownness to the diode itself, it looks the normal yellow.
At this point it seems to me like the diode, or diode-MCPCB solder connection is bad, so my questions are:
- Has anyone encountered and solved this issue, if so how?
- How can I narrow the issue further to determine if the driver itself is bad?
- Can I drop in a new MCPCB e.g. a copper backed one like a noctigon using the existing nitecore driver, assuming the driver is OK?