Purchased a new to me 2005 Ranger z19 from friend two weeks ago.  He had a reputable and knowledgeable local company install new wiring harness (similar to Sea-Clear but made by company) and new lithium battery to power electronics about 6 months ago.  The boat had his Lowrance Live 12's at bow and console with active target.

 

I had company that did previous wiring come and move my electronics, two Lowrance HDS 9 Gen 2's, to console and bow.  They work great.  I also have  a Garmin Livescope with a 106sv.  So he wires those into his harness as well.  Get everything mounted and power on Garmin head unit.  Head unit won't power on.

 

The 106sv that I was going to use had been in storage for two years.  So he and I are thinking maybe it got knocked off counter, decided to die at some point in storage, etc.  So I go to my boat that had an additional 106sv on it that has been used hundreds of times over the past few years.  I unsnap it from cradle, move it to new boat, snap it into cradle.  Nothing won't power on.   Seems I have two dead units.  

 

He takes the units back to his shop where he is working on another boat with 106sv.  The head unit from shop works in cradle, but my two do nothing.  He says I must have two dead units.  I disagree and ask if I can take his head unit to my new boat and attempt to use it in my cradle.  Sure he says it can't hurt it just to set in cradle and power it on.  He assures me this unit will work when I snap it into my cradle.

 

Well, it doesn't.  Just like my two, nothing.  I bring him back unit and we snap it into his cradle.  Now it's bricked too.  Won't power on.

 

He says cradle may be causing issue.  I took my voltage meter and checked every connection on cradle.  It matches the one in my old boat  The four pins on far right have right at 12 volts.  So doesn't appear to be to much power. 

 

Could cradle be causing issue?  Did he wire something incorrectly in his harness?  Any help would be greatly appreciated.  Thanks

You need to get a hold of garmin. That doesn’t make sense that both cradles would check out the same and it would be frying the head unit.

If I had to guess I would say he reversed the polarity when he wired it.  I don’t know if that would brick a unit.  I’ve never tried it.  Are you sure you checked the polarity correctly with your tester?

if his worked in the shop, didn't on your boat, and then now doesn't in his shop then it sounds like you fried it.  I'd guess the same happened to your unit when you plugged it in.  Just sitting in storage shouldn't have hurt it.  There isn't an internal battery to go bad.  There are no mechanical tubes that would wear down on their own.

 

Given that the other two units on your boat work, I'd be inclined to say that whatever happened to make the new harness for the 106 is the problem.  Without seeing it that's probably what garmin is going to say as well.  To test the units you'd want them on just a bare battery/wire setup so you know you're getting a single thing connected to a single 12V source.  That's what it sounds like you tried to do on the shop bench and both won't work.

 

have you checked the fuse for the 106 cradle?  Presumably there is either an inline fuse or the new harness is running power through a fuse panel.  That should hopefully prevent too much current running through the unit if it was wired incorrectly (and should have stopped it from frying).  But if for instance it ran 24V through and wasn't fused then that could be a problem...

Update: New unit from Bass Pro with new cradle. He checks all the wiring from the battery to console to bow up to cradle. Everything checks out fine.

 

Moment of truth install new head unit into new cradle and it works great. Not sure what the cradle was doing to brick the units as I tested the used cradle one more time with volt meter versus brand new cradle and voltage wise it is identical, but something the cradle was doing was screwing the units up.

 

So after hours of frustration, several days of head scratching, we are sending the cradle and 3 head units back to Garmin. He says they have installed over 600 of the Garmin head units and had never seen a cradle cause this problem.  Guess I'm just lucky. Thanks everyone for their help and input.