[ICOM] IC-W2A failure

[kk2ed at comcast.net]

Good Afternoon, 



I have two Icom IC-W2As that have failed in the same way. One a while back that I shelved, and another that failed again today in the same way.  



After plugging in the BC-77A wall charger into the radio's DC power jack, the radio will no longer turn on.  Even once the cord is unplugged, the radio will not turn on. The battery is good and has a full charge from a rapid charger. The radio worked fine before plugging in the charger. 



If I take my bench variable power supply and set it to 7v, then connect clip leads to the radio's battery terminals, the radio still will not power on.    However, when the BC-77A charger is plugged into the radio, I do see a DC voltage at the terminals which I'm guessing would charge an attached battery. The connections at the DC power jack are fine. 



Looking at the schematic, I see that the +DC line is fed into some sort of protection/limiting/charging circuit which is located on a sub-pc assembly where the battery terminals are located. I am measuring +DC into this board, and the regulated/protected "Vcc" 12v voltage is leaving this assembly and being fed to the main logic unit. 



Evidently, something is preventing the CPU from starting (powering on) the radio.  I thought I heard that this was a common failure mode for this model/series HT years ago when it was popular.   


A call to Icom amateur support wasn't worth the time involved. Unless you are calling with a simple user problem, they don't offer much support. You can't even speak to someone who does component level repairs anymore!   



Has anyone here on the list troubleshooted a similar failure in the IC-W2A series radios before, and have any suggestions?   Or seen this failure mode before? 



Thanks 



Eric 

KE2D