I have the same problem with the dsm alarm i sent unit back to raymarine to be checked and upgraded and i paid for it came back with the same problem and raymarine sold me a new DSM module still has the same problem raymarine sold me a internet cable still have the same problem now they tell me my transducer is no good what do i do now

I would think it's prity much certain that the DSM 300 is duff. I returned mine back to Raymarine for test and repair £200 + VAT They came back unable to repair as they have no parts for the DSM 300 . They undertake to be able to repair units for up to 10 years and I think that's why they offered me a DSM 30 that will work with my analog display in my case a C70 MFDU and the existing transducer. OR an upgrade to a CP370 digital sonar unit, this will work on your existing tranducer but you will have to upgrade your display to a digital unit, I went for the upgrade and purchased an "a"series 9" MFDU with a chart, fantastic performance. This has left me with a spare analog MFDU that will hopefully keep my radar running a little longer before I have to go down that road and upgrade.
Hope this helps
PS there was no extra to pay so a CP370 for £240 was a good deal

I have exactly the same problem. I have sent the unit for repair by Raymarine UK. I am waiting for their response. As soon as I have it I will posted. georges

Murray,

Has the DSM and the E120 software been upgraded to the latest software: 4.12 for the DSM and 5.52 for the E120?

Try this first. You can download the software off Raymarine.com and burn each to a separate compact flash card.

I have seen many problems like you are experiencing solved with this simple change.

If this doesn't solve the problem, the DSM will have to go back to Raymarine for repair.

I would recommend upgrading the E80 and the DSM to the newest software levels:

E80 - 5.52
DSM - 4.12.

You can download the software off raymarine.com and load them onto different compact flash cards. Both softwares are upgraded through the E80 display.

your feeling is correct on this it is still probably software! but also be aware that the power in connections are very susceptible to vibration and strains and once cracked inside they get a mind of their own. If this is a come and go problem that won't resolve, reflow the solder joints inside the DSM.

Check that there is power available at the DSM. Then verify that the DSM connector cable is correctly connected between the DSM and the C120. Finally, be sure that you have the most recent software version installed ( V 4.29). If all of that fails to bring back the DSM, try a factory reset. You accomplish this by holding down the first softkey while powering up the display. Hold the softkey until the reset countdown ends and the display begins to reboot. Be aware that a factory reset will delete any waypoints, routes, etc. so be sure to back upp anything important.

It sounds like a software issue. If the depth still shows numbers and not dashes, that indicate that the DSM and trandsucer is working. Be sure that you have the most recent software for the E120 and for the DSM. You can find info about the current software and how to load it on Raymarine's website. It is important to perform a factory reset once the new software is loaded. If that doesnt solve your trouble, you will need to consult Raymarine's tech support dept.

The only other way would be to change the PSU board in the unit. The connector back plane is connected to this board.I am a authorized Raymarine repairer. I could drop ship you the board from Raymarine and email you an instruction manual on how to change it.I am not located in the US so shipping the unit to me for repair becomes expensive.You can also check with your dealer in Seattle first but I do not think that he can buy the board from Raymarine. Raymarine policy on repairing product is different from country to country. We are on the other side of the world so Raymarine allows us to repair there product as it is to costly to ship it all back to there repair facility in the states or the UK.If your unit is still under factory warranty then if you open it it will void the warranty.So then you would have to send it to Raymarine. With a diagram if you are natural a technical person you will not have a problem changing the board.If you are technically challenged I would say send it to Raymarine. Hope this helps.

I don't have the sounder so can't address your question directly, but you can download all Raymarine manuals for your gear directly at www.raymarine.com

You have either the DSM250 or DSM300 digital depth sounder module installed. The C80 is not seeing it.

There is an LED status light on the DSM. For starters, it should be lit either red, yellow or green to confirm it is actually powered on. We are hoping for a green light.

Double-check the cable between DSM and C80 for tightness. Also double-check the DSM's power cable for tightness.

The DSM's are sensitive to voltage level onboard. Make sure the DSM's connections to the circuit breaker panel or battery are tight and clean. Double check with a multimeter the there is 12V DC available to the DSM.

Let me know what you find.