XM-L RGBW problem

Yesterday I received this to put in my 502B for fun and have a problem with driver modes not working
http://www.kaidomain.com/p/S025273.Cree-XM-L-Color-Neutral-White-4500K-Red-Green-Blue-RGBW-LED-Emitter-with-16mm-x-1mm-Aluminum-PCB-(~~1-pc~~)
http://www.kaidomain.com/p/S025274.17mm-3V-4_2V-600mA-1000mA-2-Groups-5-to-7-Mode-Driver-Circuit-Board-for-Cree-XM-L-Color-MC-E-Color-(1-pc)

I soldered it as pictures show and when I turn it on I get white color.
Short tap gives quick red blink (barely noticeable, less than half second) and goes to green.
Second tap goes to blue.
Third tap gives fast r-g-b (again less than second) and goes to mode 1 (white).

Any advice how to fix that? I checked soldering on wires and found no problems, but it’s possible I didn’t see something.

I did not know that KD lists that driver, it is the RGBW driver formerly sold by intl-outdoor, Mtn still has some for sale. This KD driver is that same driver or an exact clone, including the same rather basic firmware. Your driver is skipping modes, the question is if the mode skipping is random, which could be a loose contact, or if the behaviour exactly repeatable, in which case being in certain modes by itself triggers changing to the next mode.

Btw, a while ago I had a closer look at this driver here: djozz driver hack #2. (was: Colour driver build, based on D882 sot89 transistor?)

Mode skipping is repeatable. It’s the same behavior every time.

Looks like problem is when red led lights as it skips red only and rgb strobe.

I am by no means an electronics expert but here’s an idea that could cause this behaviour:

Whenever the red channel is triggered by the MCU, the power is drained away from the MCU, the MCU detects a tap, closes the red gate and goes to next mode, this restores power to the MCU and the flashlight is lighted in the new mode.

Something like this could be caused by an unwanted solder bridge somewhere in the red channel hardware (near the resistor or transistor)

This is all wild speculation!

Thank you for suggestion, I will try to find unwanted solder if that’s the problem.

as said, check solders and possible “bridges”. I have that led and driver in a convoy S2+ and works as expected

Fixed it today, it was bad solder connection. It was so tiny I had to use magnifier glass to find it.

Thank you for help.

For my curiosity, could you point out, perhaps with a picture or drawing, which solder connection was bad? And was it a connection that was broken, or was there an extra connection where there should not be one?

Sorry should have been more detailed in my previous answer.

Don’t have picture of my driver as it’s assembled and don’t want to take it apart now it’s working.

There was extra connection where it should not be. It was between D882 of red LED and resistor next to it. One leg od D882 is connected to this resistor normally, but solder was between other leg and other side of resistor.

I will use your picture to show it, it’s marked with red line.

Thanks, so the MCU pin for the red channel was directly connected to ground. My made-up story could even be correct :party:

Yes, you gave me good idea where to look for problem.