When I turn on the unit it will not read the depth only a blue screen and it will not let me switch out of auto mode or run the sounder test?

You need to check to see if the depth sounder transducer is connected or functioning. It might be turned off, the connectors may be bad or the transducer is bad. I don't have the 498 manual in front of me but I think there is a test function under the setup menu. I'd check my connections (the usual suspect) then run that.

Garmin tech support is pretty good/quick. So don;t be afraid to give them a call.

perhaps someone has messed with your sounder settings. You may want to factory reset the sounder from within one of the menus in your navnet. Also you may have a transducer going bad. Did you hit anything with it or run aground once? Maybe someone painted over the face of the transducer with bottom paint. There's alot of things that can cause this to happen. It would be best to have the sounder checked out before you do anything to the ducer. Remove your navnet and sounder and take it to a dealer to test on the bench. If you're in the maryland area, Mid-shore Electronics and handle this for you. Even if you're not, you can send the units to them.

check your gain setting try auto gain and try manually gaining back to see if it resolves, if yes, send unit in to furuno, if no, ducer is probably at fault.

We have an old Hummingbird Depth Sounder (Wide 100, 94 model) and it turns on but must be on test mode or smething cause we can not get it off. Does anyone know or have a manual to solve this problem. Please help.

A test bucket wont work, A 200 khz transducer will generally not work in anything less than 2' of water, due to surface clutter. If the transducer is working, you should hear it make a ticking sound.

When you got the 17000 foot reading was your range set to auto?

How is the transducer situated on the boat? Sometimes turbulence and bubbles from the hull can cause erroneous readings, including unrealistic depths, or no depth at all. Stop the boat and turn off the engin e and anything electrical to see if problem repeats itself. If it only crops up when the boat is moving then it is most likely the transducer location.

I've found this manuals in Faria's site:

Depth sounder:
http://faria-instruments.com/site_manuals/IS0091F.pdf

Bombardier Depth Sounder:
http://faria-instruments.com/site_manuals/IS0138_C_digital_depth_sounder_owners_manual.pdf

Depth Sounder, Flushmount:
http://faria-instruments.com/site_manuals/IS0141c.pdf

Depth Sounder, Flush Mounted, Remotely Switched:
http://faria-instruments.com/site_manuals/IS0229_A_Digital_depth_sounder.pdf

there are also other useful manuals in the bottom of the page:
http://www.faria-instruments.com/downloads.php

I will see if I can get mine off the hull for testing. Still have found no procedure. Thinking about just replacing the sounder with another unit.

To re-program the Si-tex CSV-106 depth sounder to feet/meters/fathoms: Push and hold down the MENU key while turning the unit on (POWER key) to enter a special menu. Release both keys after you hear two beeps, almost immediately. Use the LOWER ALARM key to select the desired unit for depth, then turn off the depth sounder. That's it, just turn on again to see the change.
There is also another menu (for testing sounder) available by pressing the MODE and turning on as above.

It is unlikely the problem is in the A65 screen.....most likely it is an issue with the paddlewheel itself, its circuit in the depth/speed transducer, or least likely, in the DSM25 sounder module.

Both the log and the trip functiions are read from the paddle-wheel sensor of the connected DSM25 sounder module and transducer.

1. Make sure you have a DSM25 sounder module and transducer with a paddle wheel (the A65 is available without the DSM25 option.)

Double check the connections between the DSM25 and the A65, as well as the transducer connection to the A65. There is an indicator light on the DSM25 to confirm it is on.

2. Make sure the paddle wheel turns freely. They tend to get fouled easily with debris and growth.

3. Make sure the A65 is giving to a reading for SPEED when underway or when having a buddy spin the paddlewheel by hand. Do not confuse SPEED with SOG. SPEED is from the paddlewheel.....SOG (Speed over ground) comes from your GPS sensor and is not used by A65 for log or trip purposes.

If you get npo speed reading at all the paddle wheel may be defective or the depth/speed transducer may be defective. See your dealer about a replacement.

Depth: Could be for a number of reasons, too deep for the sounder - check the manual for it's max depth. Dirty water, sounder unable to penetrate through to the bottom. Weed or other debris covering the transducer. Transducer on a swing mount & being pushed out of alignment then dropping back in once stopped.

Speed: Is the speed readout controlled by a GPS or paddlewheel? If it's GPS, check the power connection of the sounder, may be loose which would also cause the depth to 'drop out'. If it's paddlewheel, you're down to bad connections or faulty unit.