LMF 200/400 Setup gotcha! After visiting Lowrance Canada and spending a couple of weeks and a few replacement sensors, it turns out the problem is a small configuration issue.
All fuel flow sensors are configured by default as PORT. So you have to plug the starboard one in first, change its config to say starboard and then plug the port engine sensor in.
If you don't do this, the units shut off somehow and you need one of the GPS or FF units to configure it then.
Just thought I'd pass this along in case |