icom icf-1010 pmr issue

[m3vuv]

Hi all,i have the above radio,it has developed a wierd fault, programing is done via the rj45 mic port it ie frequencys ctcss etc,now whenever the mic is  plugged in it goes into programing mode,i have the service manual but it doesent include the schematic of the mic,its a powered electret mic ,i have a spare mic for it that i used the coily lead  from to make an ethernet cable extension,when testing i found two of the wires shorted,its wierd as it looks fine,any ideas,or a link to a mic schematic as its not clear if its supposed to be like that and no signs of any joins anywhere,unless its in the thick grommet/ strain relife part where it entered the mic body,both mikes used to do the same when plugged in,as in putting the radio into programing mode,its very odd.

[HB9EVI]

what mic do you have at all?
the standard mic delivered with this radio is the EM-99 which is declared as a dynamic mic and not electret.
though I didn't find any schematics for this mic, but the easiest way likely is to open it; much more than the mic and ptt wiring isn't there.

[m3vuv]

aparently it should be a HM-100 or an HM-152,im not sure what mine has tho as i cant see markings on it,there is a couple of caps on the pcb inside it tho on the pcb inside it,guess there filters?