Topic: 898C SI Sonar Screen is Snowy

[BrianO]

Over the past season, might be 2 seasons, my 898 sonar display has been getting an increasing quantity of noise/snow from top to bottom.  Basically dark pixels spread somewhat uniformly from top to bottom.  Depth readings are OK.  Bottom view appears normal, meaning where I expect a drop off, or sand bar its there.  I still mark fish, but it's getting much harder to read.

My use is salt water only.  No electric trolling motor, and no history of motor noise showing up on the screen.  I've had this unit since 2012.  I cannot be 100% be sure, but I think I get the snow both drifting with the motor off & trolling.  My built in to the transducer temperature sensor displays temperatures that are maybe 20 degrees colder than the actual temp.

Naturally, I've decided to deal with this now that the boat is out of the water until spring.  I don't have pictures of the display, and I do not know anyone with a Humminbird setup for me to put the unit on for a comparison.  I'm thinking the transducer is going bad, but would like some other opinions before I order a new one.  Would hate to order, install & find the problem is not solved.

Any help is appreciated,
Thanks

[rnvinc]

Have you tried Restore Defaults  ...??

Does the unit have the latest software version  ...??
https://www.humminbird.com/faqDetail.aspx?id=3648

Is the issue only on the 2d display  ...?? SI and DI showing any anomalies  ...??

Rickie

[fshndude]

Since I live here on the coast of Va./NC, have you tried to use some electrical contact cleaner on ALL of your terminals? DON'T use or push anything into any of the female terminals. On the males you can use a tooth brush and clean them gently. Then use some Dielectric grease on all terminals. In the automotive world we have all kinds of problems with corrosion, fretting of our terminals. Just might help.

[BrianO]

Have the latest software.

I think it may only be on the 2D display.  I seldom use the DI or SI, but I don't recall any issues.

Cleaning the contacts is a good idea. 

I tried cleaning the temp sensor in the transducer, but it didn't help.  I previously had a 797C2SI, and that temp failed too, but there were no other issues, so I didn't worry about it.

[fshndude]

As a after thought, cycle the connector with the cleaner on the terminals.

[BrianO]

Finally back in the water.  Pics follow.  GPS screen is fine.  Not sure if I'm getting interference or if it's debris suspended in water.

[ Specified attachment is not available ]

[rnvinc]

Debris would only be in the water column on the 2d display  ...

This anomaly continues down past the bottom detail  ...

Did you try Restore Defaults  ...??

Rickie

[BrianO]

Don't remember if I did or not, but I'll try it. 

Good point on the debris.  Think the unit has always showed some stuff below the water column.  Figured it was a second echo or something.  Seems to have gotten worse.  Don't really want to haul it out of the slip to deal with this, but I may have no choice if it's the transducer.

[BrianO]

It's some sort of noise from when the engine is running.  Did a drifting fishing trip, and it looked normal when the engine is off.  Never had this problem before.  Then I realized this is all new since I repowered my boat.  Noise only appears on sonar screens and not on the others.  At a loss on how to fix it.  Only have 1 battery, and no room for a second dedicated to electronics only.

[rnvinc]

It's some sort of noise from when the engine is running.  Did a drifting fishing trip, and it looked normal when the engine is off.  Never had this problem before.  Then I realized this is all new since I repowered my boat.  Noise only appears on sonar screens and not on the others.  At a loss on how to fix it.  Only have 1 battery, and no room for a second dedicated to electronics only.

Engine interference encroaching can mean that the xducer cable is too close to the engine wiring harness  ...

If there's a nick in the xducer cable this can be even worse allowing interference encroachment  ...(Insure to also inspect the rubber strain relief where the xducer cable enters the xducer housing - the rubber can Crack over time)  ... 

It may be a good idea to completely remove the xducer and inspect it and the cable for damage  ... and then reroute the cable away from engine wiring upon re-installaion  ...

Rickie

[BrianO]

Engine interference encroaching can mean that the xducer cable is too close to the engine wiring harness  ...

If there's a nick in the xducer cable this can be even worse allowing interference encroachment  ...(Insure to also inspect the rubber strain relief where the xducer cable enters the xducer housing - the rubber can Crack over time)  ... 

It may be a good idea to completely remove the xducer and inspect it and the cable for damage  ... and then reroute the cable away from engine wiring upon re-installaion  ...

Rickie

Rickie, it was water getting in around the rubber boot.  Replaced the transducer, and I'm back in business.  Thanks for your help.

[rnvinc]

Rickie, it was water getting in around the rubber boot.  Replaced the transducer, and I'm back in business.  Thanks for your help.

I have also experienced these cable strain relief issues  ...

Rickie