Hmmm, that really is odd. So it doesn’t immediately go to turbo and stay there? It actually ramps up and down and switches modes on it’s own?
My guess would be there is something shorting the driver circuits. Maybe a stray sliver of aluminum or something. You might try pulling the driver out and run a brush or compressed air over the tiny components.
I assume you checked to see if the driver was flat and that the notches line up, then make sure the retaining ring is tight.
No, it does not go to turbo. When holding the switch, it goes to different levels in steps, stays at the brightest. After that, it step-ramps down if i release the switch and hold it again. The driver is flat, however the notches do not align perfectly, so maybe there is a short between the case and the driver? !Imgur: The magic of the Internet! In order to pull out the driver, I assume I have to desolder the wires at the front, right?
No, it does not go to turbo. When holding the switch, it goes to different levels in steps, stays at the brightest. After that, it step-ramps down if i release the switch and hold it again. The driver is flat, however the notches do not align perfectly, so maybe there is a short between the case and the driver?
In order to pull out the driver, I assume I have to desolder the wires at the front, right?
I don’t think it’s dirty threads as it also happens when I directly connect the battery to the spring and case. I don’t see how the threads could be involved.
What your describing sounds like proper normal function. It ramps up when you hold the button, release and press again and it goes back down.
Are you confused that it goes in steps instead of the smooth ramp? To switch from stepped ramping to smooth ramping turn the light on and do 3 fast clicks.
Well, it turns on immediately when inserting the battery and tightening. And I can’t turn it off. It acts like a twisty.
I have pulled out the driver and cleaned it. Re-inserted it taking care of the notch. Same result :-(.
I am clueless. Somehow, the MCU must be working as it’s doing something when pressing the button. The button must also be working. It almost looks like (on of the) 7135 are permanently working so there might be a short somewhere?
Try unscrewing the head and tail cap, screw in the tail cap nice & tight, insert battery, then screw in the head nice and tight. Or try the reverse of doing the head first, then tail. Of course, just be careful of the tail cap as the switch board and button will fall out (not secured in place at all).
I had a similar flaky operation before I did this. Now my FW3A is working great.
However it’s happening with the head only when connecting + to the spring and - to the body. So that would narrow it down to the driver board. I desoldered the star, the driver board looks good. Hard to debug though.
Yeah, in reading what you posted about a moment ago, it does sound like there’s some kind of electronic defect going on with your driver board. Probably too expensive to mail back, unfortunately.
In order to turn the light on directly, the retaining ring would have to be making contact with the signal ring on the driver, they should be 2 different circuits right?
My FW3A started ramping up and down as soon as power was connected when it arrived too, I tightened the driver ring, pulled the inner tube out and made sure it was clean and reassembled the switch assembly. Problems cleared right up.
If one of the amc7135 chips is dead, it could cause behavior like that. Those chips fail open, meaning they allow current to pass through… so it would be always on. But the other chips would still work, so it could still sort of function.
Not an EE but I presume one could verify that with a multimeter probing between the pins? How does it fail i.e. what pins to check? If I would have to guess, let’s say VDD and OUT?
For reference I checked a couple of 7135’s on my E2L
VDD - GND ~61.6K
OUT - GND ~0.54M
VDD - OUT infinity
Wow, I think you are exactly right. Basically the light works including ramping etc., the problem is just that “off” level is not really off. Hitting the switch once goes to a brighter level (“on”), hitting it again to the lower level (“off”). This is exactly the behavior I would expect from an open 7135. I just didn’t know that they fail open.