Issue with TK40 driver; replaced MCE for XM-L but driver is constant on high

Hello, Houston you 've got me puzzled....



I thought it would be interesting to replace the MCE for a XML in this flashlight. Replaced the Led on star, glued with arctic silver and soldered the leads back on.



The moment it gets powered by twisting the batterycap on, it is constant on.

I can not get it off, or change mode.

The moment I change mode it flickers/dims half a second later, but instantly goes back to high. (well, I guess it's high, no modes to compare to.)



I did not expect did to happen.

What could be causing this?

Is the driver laid-out for the MC-E characteristics?



As far as I can trace back no wires are damaged or other things are different other then the Led.



Probably will end up glueing hte MCE back in.

But anyone a clue or suggestion ?

Bump. I was thinking about changing the emitter on a TK30, but I know nothing about modding (how to take head apart on the TK30 and what emitter would/could swap with the MCE).

MCE is higher Vf (6), XML is lower (3) mismatch between driver and led Vf