Sorry, if it's not in fw or in the units' diagnostics pages I can't help. Similar problem with 310 series as discussed in rambling fashion in the PCB P/N thread from this post on: [Only registered and activated users can see links. ].

Maybe you could try to convert the Approach to an Oregon x00 rather than an x50? In the junior model fw the PCB P/N is 105-01356-00:

f57q