20 Most Recent Garmin Gpsmap 498, External Antenna With Dual Frequency Transom Mount Transducer Questions & Answers

It's probably the ccfl is burned out. The illuminator is a very interesting (and very thin) little contraption. Inside the illuminator is an L-shaped ccfl (cold cathode fluresent lamp.) They run at very high voltages. Eventually the ccfl burns out.Go to www.ccflwarehouse.com. They can fix you up with a mail-in replacement for around $35.You can read about my experience at www.catalina22experiment.com Best,Zig

What version software are you running in your 498?

I have a very similar problem. Unfortunately my boating season is over until next May. I found I was at software rev 2.30 and should be at 3.40 Some of the software updates were to resolve sounder problems.

the blinking indicates a satelite not finding you. push the done button for that location and the Garmin should reset itself. don't start the garmin inside any garage.

kdog

Here's the link to download the manual for free. If this solves your problem, please come back and rate our solution.
https://buy.garmin.com/shop/shop.do?pID=370

Hi
Sure you can use an external antenna.
Here it is
It is however really only useful to allow for decent veiw of satelites when the unit is monuted under a the signal shadow of a cabin or below decks. Any GPS will not perform as well if a decent shot of 3 or more satleites is not acheived. I suspect this is what is hampering your device. Using the external antenna mounted to get maximum view of the sky will eliminate any such issues for you.
Please take a moment to rate this solution. heers
regards robotek

you can find it here www.garmin.com

All transducers should read 0 ohms or close to it. If not you most likely have a broken pin in the connector or wire.

I can't remember correct setup but make sure that box is powered and connected to GPS in right input. With no power to box it won't be discovered by head unit.

Place your ear against the transducer with unit ON. You should hear it 'tikking' ( tic tic tic ) then the transducer is ok...

garmin_products_out_of_support_list_20140207 Here is a pdf for Garmin. you should be able to contact them though email. Good luck

https://www.garmin.com/en-US

Check you transducer cable route and connections. Look for kinks, punctures, & tears in cable. Visually check the transducer for damage. #2 check the units operation on a friends boat with the same set or research a local marine repair shop to check ops. Best of luck on the problem.