Humminbird 788c trouble

[Bobber]

I upgraded from a Humminbird 565 to a 788c sonar/gps unit this year and have had nothing but one big headache. When I changed them out I decided that since the new unit had the exact same transducer as the old one I would just leave the transducer on the boat. Everything worked fine for a couple quick trips, then the sonar quit working. Put the new transducer on and everything worked fine. Took a buddy of mine up to Seneca and after two hours, the sonar quit working again. Called Humminbird support from the boat and they had me change a bunch of settings trying to troubleshoot the problem, finally they said must be the transducer, we'll get one out via fedex today. Got the new transducer, everything worked fine. Took my buddy up to Cayuga, trolled for six hours, lost the sonar again. Called Humminbird support and told them everything that has happened, this time they asked me to send the whole unit back to them for testing, just got it back...with another new transducer. I have a hard time believing that I could get this many defective transducers in a row. I'll be curious to see how long this one lasts...so far I've been getting an average of ten hours out of each one. According to the one system screen...unit has 30 hours on it...and I've gone thru 3 transducers, just put fourth one on. Just curious if anyone else has had this kind of trouble...or if anyone has any suggestions as to what could be causing transducer failure.

Kyle

[Schools Out]

I have the exact same unit and its been nothing but good to me.

no clue on the transducer failure though

[Splitshot115]

Bobber,

Check the routing of the transducer cable, might be close enough to something that it shouldn't be. I had one go bad on a bird, so the next one I put in I cahinged the routing of the cable and haven't had a problem since. Don't know if it was to close to battery cables or other electrical components, but moved it away from them and haven't had a problem since.

Splitshot115

[Bobber]

Never gave it much thought Splitshot...I'll have to give that a try. Wouldn't think something like that would cause any more trouble than some interference...but who knows. Thanks!

Kyle

[muskybob]

Also make sure you don't have your transducer wire coiled into a circle. Coil it in the shape of an S.

[NitroMusky]

assuming you have to re-run the full length of wire for each new transducer and checked for cuts etc, (which would eliminate a wire problem), my guess is the 'ducer was (is?) getting sent too much power - not enough to fry it but enough to 'slowly' burn it out. I'm not sure what voltage the head unit steps the power down to for the sonar (if at all) but maybe a bad voltage regulator. either that or a very intermittant internal short in the head unit on the sonar circuit.

net net: its the head unit...there is no way that you got 3 bad ''ducers in a row....but on the off chance they are, you need to get a lottery ticket quick!

good luck

NM

[stan]

I have had the 787 for over a year with no problems myself. But have heard of a few friends with the same unit as mine that had to go to a heavier ground wire and then there problems where solved