Well I changed the power unit first yesterday and that didn’t help. Neither did the power cord and actually at this point the mount even refused to connect. So I had not high hopes when I changed the Y cable but miracles happen and with the new Y cable everything worked fine last night.
This until an hour ago when I tried to start a sequence again only to run into the same problem again. When the mount is connected, the RA axes immediately slews about 20 degrees after which it stops and the yellow light is on.
If I try to open the RA gearbox tomorrow, what exactly should I look for?
