Troubled fishfinder
 

Need some assistance: I have the Lowrance M68C Fish Finder/ GPS unit. Today, when fishing at 184 ft depth, the FF unit suddenly started flashing, the screen went clear, and the depth went from 184 ft to 5 ft. After that, nada, except when heading back into the harbor my depth gauge registered 225 ft when in fact we were in only 25ft of water.

I don’t know if it’s the transducer or the head unit has gone belly up? Anyone else out there ever experience anything similar? The unit is only 3 months old.

Sometimes, FFs turn quirky when getting low or unstable voltages.

Check the voltage of battery at the terminals and then the connector ends. With an SLA, you should get a reading of about 12.7 volts. If you are getting less than 10v with no load, that battery needs charging, or may already be dead. If you get a good reading at the terminals, and a lower one at the connectors, the connectors are corroded. Sometimes, they can be polished up, other times, you need to change them.

Next, put the battery in, but not the head unit. Check the voltage at the pins that go into the unit. You should get a reading that is equal to what it is directly at the battery terminals. If not, there is something wrong along the power lines. Its either corroded connectors, corroded or bad fuse contacts or black wire disease (blackening of the wire due to saltwater shorting). Check the voltage at different points along the power line too. Particularly after each connection point (butts, connectors, jumper). If you have to, cut lightly into the wires so you can insert a DVM probe. Tape the cut close when finished.

If power problems are ruled out, send the head and tx unit in. Its under warranty, so its better that the company check it out.

I just solved a long standing problem with my ff. It likes to turn off on the water or sometimes not turn on at all. Found out that a perfectly good looking connector develops enough resistance to drop my voltage from 12 volts at the battery, to 6-7 volts at the pins. Change the connector, and she ran fine.

/bing

I have an eagle 320c. I works great most of the time. However, once the female side of the pins rotted out and once my transducer came unglued from the bottom of the boat. The service wasn't real good either. I now use die-electric grease from the auto parts store on all my electronics as well as contact cleaner spray. Sometimes, a little sandpaper on the fuse will do the trick. sundog

:iagree:

If your electrical checks out, try re-mounting the transducer. You may have an air bubble or a gap in the silicone.

It may have jumped to simulator, that unit will, when not getting a reading for 30 seconds or so. You need to go through the menu and reset it manually.

Thanks Andy. I set it back to the factory spec's on Friday and went out fishing yesterday. It seemed to be ok. A couple times the depth finder went a little haywire with incorrect depth readings when I passed the 200 ft depth. And only once did the unit powered off. But at least the screen did not clear! Thanks again. Roger

Roger, you don't need fishfinder if you are fish magnet :the_finger:

I need all the help I can get! :cheers1: