i had this on my previous 40... although all i could determine was a ground wire from the filter light (not the glow light), went via a push button to ground..
this meant that the normal glow timer would work first, or if it decided not to work (which happened after a while), you could manualy glow it for a few seconds.
this mod seemed to disable the filter light from working though (it had never worked on that bj42)..
I might have a deeper look at this when time allows to figure out if that is all the PO did with teh push button, as I like the idea of teh timer/push button override.
Thanks for bringing this thread back up brownbear and thanks to Greg_b for the tech details.. !
