I've seen this posted a few times but can't remember the results.
My bow mounted HDS5 blinks on and off at night when I turn on my NAV lights. I am thinking I am using the NAV light ground but haven't opened it up yet. I hope this is enough info.
Any ideas would be helpful. Thanks,

Possibly you're having a low voltage situation and the unit is on the verge of shutting down!

C.

The unit is shutting down and restarting over and over. It never gets totally on to the point of hitting enter. I don't think it is a battery voltage thing cause the big console unit is not affected and the Hydro Wave unit sits next to the problem unit and is not bothered. Thanks,

Just because the console unit is not affected does not mean there is not a voltage issue! There is a lot of wire and many switches/connections/splices between the battery and the bow. If any of these deteriorate just a little, you can lose enough voltage to the unit to cause a problem.

Your hydrowave unit may not have the same input voltage constraints that your sonar unit has, so that alone doesn't mean there is not a voltage issue here.

If you haven't already done it, set up your unit to display voltage on the screen. When the problem starts look at the voltage display and see what it says!

I'm speaking from direct experience here as I just fixed that exact problem on my boat -- after a few minutes the front graph would blink on and off. To trouble-shoot, I turned the unit on and observed the voltage reading, Over the course of a few minutes the voltage display got lower and lower unitl it reached a point that the unit started blinking.

In my case the fix was to run a complete new set of wires (BOTH negative and positive) from the battery to the bow and connected the sonar unit to that through an accessory switch. What this does is bypass the boat wiring and all of those switches/connections/splices and eliminates the bad connection from the circuit (wherever it is --- I never found the actual bad connection).

If you wind up doing the extra wire thing, be sure to install a fuse in the wiring near the battery! I'd also recommend using at least 14AWG wire for this application.

If it turns out that voltage is indeed not your issue, the only likely choice is to call your sonar manufacturer's customer service and see what they say.

One other possible trouble-shooting idea -- is it possible to temporarily swap your bow and console units? If the symptom moves with the unit, you have a unit problem. If not, it is definitely a boat wiring/voltage problem.

Hope my recent experience is useful to you.

C.

I had a brand new HDS-10 going into a re-boot mode. Mine turned out to be a problem with the unit itsself. Sent it back to Lowrance and got a new one (or same unit?) back within a week.

The way I was able to determine my problem was to swap places with my bow and console units. Turned oout that the 10 on the bow started the rebooting thing no matter where it was located.

Good luck...

Just had the same problem. Voltage is low. Recharge and you should be fine.

I ran 2 new 14AWG wires from the battery to the bow unit and it now matches the higher voltage at the console.

Thanks for the advice everyone.