Topic: 737 screams, won't see map, max 32ft on either puck

[tambrose76]

737 only 170 hrs, great condition. battery 12.6.  defaults or not, wideside or quad puck, will not see over 32 ft and rarely a fish, even with all alarms on. all other features appear fine and adjustable.  wont see lakemaster 2.0 chip but maybe not compatible.  occasionally, while setting features, sets off to screaming alarm med tone that cannot be shut off other than by removal of 12vdc.  hate to send it in for $105 check-see.  tried to reload latest DIN 4.960? file but says is already set; how to cold boot and reload software again; no PC cable, just SD card load and go.  argh...

[Humminbird_Greg]

Even though the battery may be at 12.6 volts the 737 unit may not be receiving that voltage and/or it may not be getting the current that it needs to operate correctly.  One of the signs of that is low sensitivity or not being able to read in deeper water.  Check all of the electrical connections between your unit and the battery.  Don’t forget the fuse, fuse holder and battery contacts.  Nothing loose or corroded as this will rob power from the 737 unit.  Even better would be to cross-test your unit on someone else’s boat that is running a non-DI model Humminbird unit as all use the same basic 200kHz 2D type sonar.  This will show where the problem is: unit or transducer(s).

No, the 737 is not LakeMaster map card compatible.

Since your unit already has the current 4.960 software in it you would have to load an older version in first and then follow that up with (new download of) the 4.960 software again.  I will caution you though that loading an older version of software could cause problems with your unit.

[tambrose76]

Thanks, Greg!  Say, I got a brand new battery feeding fresh juice to the unit, took it to the water, tried both wide side and quad transducers again, STILL get the exact same situation-- reads 30-32 ft in proper setup, demo off, sim off, then it jumps to 19ft and back to 32ft again.  Noting, removal of the transducer connection to the 737 directly does NOT chg the view; it is as if the transducers are never seen.  I wonder if that *good looking* center pin ground (4) is not connected inside the 737 head.  No splay to the socket, both male pin setups of transducer cables are fine. 

The transducers certainly BOTH cannot be bad somehow, as I take care of them like infants.  Ground seems to be the only common (pun) tie.  Is there an expected resistance read between GND and the other head pins on the 737 that would allow me a sanity check?  Pin 4-1, 4-2, etc.?  I am an electronics tech.

[Humminbird_Greg]

Sounds more like something inside the unit has let go tambrose76.  Those two transducers should share several different pin connections and it would be rare for both of them to have failed in this specific of a way at the same time.  Know anyone you could cross-test units with just to be sure it’s in the head unit?  Just about any Humminbird model that will plug up will work for this as long as it is not a DI model unit.  Even an SI model unit will work for the test.

No, no pin-to-pin connections that you could check that I know of.

[tambrose76]

I will take the transducers to my other boat in the southern part of the state and try them on the 898.

[tambrose76]

This 737 never got any better.  It is on the HB hit lilst for "we no fix anymore."  Sent it to Ontario for repairs, as they yet perform supposed magic. New WideSide transducer acts as if it is never seen by the head, which works in SIM perfectly. Puck on, puck off, wildly shifting NORMAL depth readings in 14-50fow. I did the pinouts test between a WideView, 581i, and the 737 if anyone wants continuity information. 

[tambrose76]

   Note-- sent in for repairs and found connections splayed for puck.  Brand new WS puck was only 80% effective, per testing, though just out of OEM box.  Works like new.