Bad Mega SI for Gn2 transducer??

[cfarmer]

hello All.
i have a helix 12GPS SI G2 which has th XM 9 20 MSIMega Transducer at the transom. been having an issue with the image going from bright clear sharp image, to very dark and Almost impossible to see, this happens on both down and side imaging, 2d sonar seems to still work fine, is there some type of test I can do to confirm this is a transducer issue? I don’t want to spend the money on a new transducer and find out that’s not the problem.
this problem comes and goes, unit might work ok for an hour or two then the screen goes dark, you can still see a faint image but its realy not usable at this point.
I also moved my helix 9 from the bow to test at the console and got the same results. But is there anything else I should check or test before I go looking for a new ducer?

[ezfishn]

If you swapped units and got same results then most likely transducer. They can degrade over time. The only other thing might be whether you have good power at that location.

[RL56]

Recently my Helx 10 G2N SI screen went dark you could see a SI image in the background but the view was not useable. Bought a new transducer did not fix the issue. Contacted Humminbird and paid the fee to have it repaired. Got unit back and they had to repair the board in the unit. It would be nice to find someone with a working transducer to try before having to pay $300 + repair bill to Humminbird.