Reverse polarity damage in garmin striker dv

[Aubri]

I have a garmin striker dv that has given me reliable service for years. Today I was in a hurry to get out and go fishing and put a new battery in the boat. The motor went down right and I assumed the polarity was correct. The starter spun without engaging. To check system voltage I tried to turn on the sounder. Nothing. I determined that the starter bendix was working and realized that the battery polarity was reversed. The engine started and I untied and began turning on instruments. The plotter came on but the sounder was dead. I checked the cables in the back of the sounder and they were plugged in all the way. There is power at the fuse rail, the fuse is fine, the negative bus is fine. But the sounder will not come on. I fish for a living and not having the ability to see what is going on down there renders me blind and would leave me wasting fuel and time playing fish bingo. Is it toast? If so what specifically is toast inside the sounder? I have a soldering iron and access to components, but not the kind of deep pockets that technicians and electronics dealers require.

[MN Fisher]

Realize that most modern electronics use Surface Mount technology...not the Through-Hole of the olden days. Allows them to fit more components per square-inch on the board. Unless you're proficient, and have a FINE tip soldering iron...I'd send it in to be repaired.

[Aubri]

10 hours ago, MN Fisher said:

Realize that most modern electronics use Surface Mount technology...not the Through-Hole of the olden days. Allows them to fit more components per square-inch on the board. Unless you're proficient, and have a FINE tip soldering iron...I'd send it in to be repaired.

That's what I was afraid of. Thanks for the advice!

[MN Fisher]

2 minutes ago, Aubri said:

That's what I was afraid of. Thanks for the advice!

The worst part is - those boards are so complex that the main way of fixing the units is to test the boards, find the bad one, and just replace the board...plug and play repair. They don't even really repair the boards...just toss the bad ones.

[haggard]

16 hours ago, Aubri said:

There is power at the fuse rail, the fuse is fine, the negative bus is fine. But the sounder will not come on.

Is it possible there's another fuse in line somewhere? Maybe on the inside of the unit? 

[king fisher]

Trace your wires back from the sounder, and make sure there is no inline fuse burned out before sending in for repair.  Most have a fuse inline on the positive wire.  People hook up batteries wrong all the time.  That is one reason why all radios, Plotters, fish finders, bilge pumps, and other electronics are fuse protected.