Re: B&G Sonic Speed failure
Had already bought replacement transducers from Maxmarine and was planning to install them but halted that project when the existing ones checked out okay at 111kΩ and so I started suspecting the PCB. I'll try filling the transducer recess in the hull with silicon (to replace the missing neoprene cap) as you suggest then test with a water filled pipe. If the AGC voltage checks out okay and I still can't get the system working I'll replace the transducers.
With regards replacing the transducers: I've tried to find where the cables enter the boat but so far without success. When replacing the transducers, do you attached a pull through at the electronics box under the saloon seat and pull it through from there as you extract the old transducers or is there some other access point for the transducer cables one works from? As I understand the transducer cables enter above the waterline so the transducers should not be sealed in their tubes.
SV Wilna Grace
Amel 54 #58