LX-5 How to Diagnose a Short?

[gorf37]

Hi Everyone,

I've loved my LX-5 these past 3 seasons, but this, its 4th year, has been a tough one.

First, my charger went caput,  and even though I didn't trust the green light on the indicator, I took the unit out on my first trip of the year - and darned if the weather wasn't -35C!  The battery froze, deforming the top and bottom of the battery case, so it had to be scrapped.  I've since replaced the battery, and the folks at Marcum sent me a new charger for free!  Nice guys!

The most recent trip out, it started acting up a new way I hadn't seen before.  When turned on the motor revs up strong and sounds normal.  The red ice line shows up, and at least initially when its turned on, everything flashes a reading as if it was going to turn on normally, bottom's in the right place, nothing's bouncing, etc.  But as suddenly as it appears, the image then disappears.  The red line of the ice is still there, but nothing else, in any depth setting.  The motor continues whirring-away, and doesn't sound unhappy.  When I fiddle with the transducer cord, the image will flash onto the screen and then disappear, making me think there's a short in my transducer cord.  I've also read that the contacts on the depth scale dial can wear out.

Is there an smart, sequential way to diagnose this issue?  I'm starting to smell that I'll be sending it back to Marcum in the Spring, but the end of my season is still 3 months away, so I'd like to limp until then if I can.

Thanks for reading!  Any/all feedback is appreciated!

Gorf

[3300]

use a digital meter on the battery during charge to test the charger and after it's charged to test the battery. then turn the unit on and retest the battery. the charge voltage rate should be 14 volts. the battery after it's rested should be 12.5 to 12.6 volts. after turning on the unit and let it run for say a half hour should still be 12.5 12.4 volts.

check the voltage when it quits drawing what ever it draws. you can test it at home. you can get a free digital meter from harbor freight with their coupon or spend 6$ for it.

it sounds like a bad charger to me.

you should look into a battery tender jr charger anyway and know you have a good charger instead of the free junky chargers. i had a wire fire from one of those and if i wasn't here watching it, it could have burned the house down!

[gorf37]

13.18V on the charger with a green light.  How long constitutes resting?  I'll carry-on with that process and report back.

I got to see it with a bad battery when my charger broke, and it doesn't seem right. 

Are end to end checks of the transducer cable possible?

[3300]

no meter tests for the transducer. only thing for that is the hard floor bounce test. have the ducer hanging over a hard floor about 3 feet and look for it to show on the display and move it up and try it again. the gain shouldn't be more than half way and try it on both beams if you have dual beam. you can do this while doing the rundown test.

the resting is to allow the battery to drop down to it's shelf charge. should take 10 minutes or so and be 12.6 volts.
what your avoiding is not to get a reading while it is still dropping to test the next stage.

just let it run until it quits and then get the battery reading for the last test. it would be best to get it cold like your using it outside. so maybe let it run down outside.

your trying to figure out two things. one is how long does the battery last or if it lasts for a reasonable amount of time or not. and if it's not the battery when it quits, it will let you know that there is some thing else wrong.

you should find out what the volts of the battery is while it is a red light tho. it needs to get up to 14 volts.
so the green light voltage was right after it turned green or after it had sat there for some time?

[gorf37]

I had no idea about the hard floor test, thanks for that.  For some reason I felt the flasher didn't want to run out of water for long...

Rested ~22hrs: 13.15V
Running initially: 13.1V
Running ~2hrs @ 10C: 12.5V
Charging(red): 13.5V

I noticed that when I turned it on the motor started whirring immediately, but the clicking of the sonar didn't start until I had moved the transducer cable.  That said, once I heard the clicking start I hovered it over my plywood floor and got a return, and its depth 'halved' appropriately when changing from 20 to 40 to 80.

May get a chance to get out after the kids go down tomorrow, so I'll give er the ol college try if I do.  Thanks for the replies 3300!

[njsfishon16]

From what I read above, it sounds more like an intermittent transducer cable.  It also may not be an intermittent short; it could be an intermittent open circuit.  The fact that you area getting a light at the zero mark tells me that the transmitter in the flasher is working. 
A good way to test the transducer is to rub the face of the transducer briskly with the palm of your hand.  It should cause flashes all over the dial.  If it doesn't show any or just a few flashes, it's probably bad.  Check the transducer cable for any pinches or cuts.
I hope this helps.  I used to be an authorized warranty technician for Lowrance and Eagle as well as Raytheon back in the 80's and fixed many flashers back then.  Good Luck.

[3300]

i agree with the transducer being at fault. i don't like the voltages from the charger either. the battery tender jr is a better way to go or any name brand smart charger.
i would call marcum next to see what they suggest. you might be surprised.

1-888-778-1208
1-763-512-3966

[gorf37]

Thanks for the feedback guys, Marcum replied to my email and offered that if I ship it to them and pay their flat rate service charge, they'll give me the new transducer for no additional cost - kind of nice since the ducer is worth more than the service.

I haven't exactly been kind to my transducer cable.  It has 'dangled' during short trips between holes more than once.  Not that it's my norm, but it does happen, especially when fishing in cold weather when I don't want to grab the wet cone and get my gloves wet.  I guess this'll be my lesson to be more diligent.

One contributor that I can't control that I think may have had a big impact is ice forming on the cable.  Dipping in and out of holes in cold weather, I've occasionally built-up ice balls up to 2" diameter on the cable.  They often leave me thinking that the cable is getting crushed by the expanding ice within the centre of the ball, or if nothing else, the tension is acting most severely at each end of the ball.

Thank you for your help!  I'll give an update about limping my partially failed ducer along through this spring if there's anything noteworthy to share.

[3300]

you know you only need the very bottom of the ducer in the water and that is what marcum recommends in their manual right?

it helps land fish if your using one hole by having no cable in the water at all. this will help with the ice accumulating on it. maybe look into a wax or some thing to bead water faster on the sides of it like armor all or pam.
if the ducer is slipping down, try wrapping the cable around the arm more like 5 or more times, but be careful when your done to not pinch cut it if the cable it still wound on it. i have used velcro one wrap on the arm to keep it from slipping.

some have used an epoxy to build up the cable to puck area to make a home made strain relief.