My lowrance 522c has never worked quit right i switched the head unit out 4 times and downloaded the new software to fix the sonar digtal reading problem were it just flashes or the screen just stop scrolling i am wondering if there is something i can try-

Pay attention if depth readings shift during times when moving from spot to spot at higher speeds. If this is the case then you have air bubbles disrupting your sonar signal causing inaccurate readings or a loss of bottom lock for the unit. If over this weeds in shallow water, this at times creates havoc with sonar readings because of the wide variance of signal returns.
check the voltage at the head unit.You should have a minimum of 11.7 volts. 12.5 to 13.5 is optimal
lower power input can affect the overall performance of your unit.

Try page 212
http://www.lowrance.com/Root/Lowrance-Documents/LMS527-522_0152-181_120406.pdf

Sounds like you may have an issue with low voltage to the unit. First verify your battery is in good condition. Connect the new power cable directly to the battery using appropriate fuse and test. If the problem goes away then the problem is with the wiring between the battery and the head unit.

Chances are your GPS puck antenna is bad. They have a pretty bad rep for failing and since its now at least 5 years old , you have been on borrowed time. You can get replacements on Ebay. Your temp issue is unrelated . Might be time to upgrade.

I'd suggest calling Lowrance.. Those guys are very helpful with step by step support... I just purchased a used boat with a 525c df on it and been troubleshooting some problems with it. Central time zone and best to call right when they open or turn on the phones at 8:15.

Hello. Your observation is spot on and it is actually a characteristic that is always true when using sonar. Yes, your Lowrance uses the same sonar as a nuclear powered submarine does. The two factors you focus on, water depth and boat speed are perhaps, the two biggest factors when it comes to the quality of the fishfinder. The boat's engine should be in gear at an idle or just above. Experiment with your boat to find the best throttle location for good arches. Usually, a slow trolling speed works best. The depth of the fish can determine if the fish will arch on the screen. If the fish is in shallow water, the fish is not in the cone angle very long, making it difficult to show an arch. Typically, the deeper the fish, the easier it is to show an arch.
If you would like a complete tutorial on Lowrance sonar, go to this link. Enjoy. http://www.lowrance.com/Support/Tips-and-Tutorials/Sonar-Tutorial/

I havew a Minn Kota trolling motor on a Z21 Ranger. Minn Kota has a built in (puck type) transducer on the motor. I have a lowrance 135x on the front. The lowrance will read the temp but will blink the depth. I switched out the depth finder with another 135x with the same results. I have a 522c gps unit networked together and mounted on the console that works fine. Any suggestions on the problem with the 135x?

If it is normal in deeper water, it is most likely just returning stuff in the water (debris, algae, anything floating around...choppy water can cause this). Try installing the latest updates from http://www.lowrance.com/en/Downloads/Product-Software-Updates/

If it doesn't help, adjusting the sensitivity or setting the SURFACE CLARITY option from the SONAR FEATURES menu to LOW, MEDIUM, or HIGH...whichever gives the best results.

I hate to be the bearer of bad news, but it sounds like your internal module is on the fritz. I am pretty sure you can buy a external puck and a harness and it will work perfect. I did that with my hummingbird 997.

Probably not. Usually the transducer is made specifically for the head unit it is designed for. More often than not, transducers are not interchangeable, particularly across brands. Also, for best results, you really want to install the transducer that came with your new lowrance. That will give you the best results and sonar clarity.

Hope that helps!
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