Blowing fuse in lowrance 520c

[scott-z]

I was wondering if anyone had a clue as to what my problem could be. I wired my Lowrance 520c in according to the wiring diagram in the book and ran it to my fuse panel. It worked great until I went to trim my motor down, when it blew the inline fuse that I have wired in between the Lowrance and the fuse panel. Any ideas what I might have wrong?

[fishwater]

My guess is that when you release the trim switch, the graph circuit gets a voltage spike. Sounds like you have your graph wired in parallel to the trim? If so, the graph and trim (while running) together have less effective resistance than the graph alone, that transition when the switch is released is likely the problem. I might be mistaken about the circuit. If you remove the fuse you wired the graph and in-line fuse to, does the trim stop working?

[leech~~]

Don't you have any post on your panel marked Acc? You need to find the accessaries post and not use one that goes to a main power user like the T/T.

[scott-z]

I just went out and looked at my motor. The trim/tilt is not wired into the fuse panel at all. There is a set of heavy cables going directly from the starting battery directly to the motor. This powers the starter and trim/tilt. Then there are 2 smaller wires going directly from the battery to the fuse panel. The bilge pump and lights are wired to the panel and I have never blown a fuse on either of them. This is not a factory wiring job...the guy I bought the boat from did it himself. Any other ideas?

[minneman]

sounds very similar to a bad battery and too much voltage loss when trim is used, or motor starting. try bypassing the fuse pannel and run a wire directly to the starting battery from the 520

[scott-z]

That was my first thought. I put a new battery in last year and it still happened. Right now I am running the 520 off of my trolling motor batteries. I was just hoping to clean all of the wires up by running them into the fuse panel. Thanks to all for their input.

[Dave]

Try connecting to the bildge pump fuse and see what happens.

[scott-z]

I hadn't thought about that, I'll give it a try. Another guy I was talking to suggested a circuit breaker inplace of the fuse, then I would just have to reset the breaker.

[Dave]

And, double check that you're replacing the fuse with the correct amperage size.

[leech~~]

I hadn't thought about that, I'll give it a try. Another guy I was talking to suggested a circuit breaker inplace of the fuse, then I would just have to reset the breaker.

Scott, that's bad advise. Find and fix the problem, just don't make it easier to keep resetting it when she blows! There is a reason it is getting hot and you don't want to be out in the middle of a lake when the real issue shows it's slef with a fried bunch of wiring!

[walleyemaniac]

Why is there two small wires coming from the battery up to the fuse panel? Is one of them used for a common ground for everything or are they both hot? Need a starting point. And how did you ground your 520, into the wiring that was there or just connect it somewhere on the metal of the boat?

[scott-z]

There is a black and a red going from the negative and positive terminals of the battery to the fuse panel. Is this correct? I am not sure if there is a ground wire coming off of the 520. I thought it was just a red and a black.

[walleyemaniac]

So the negative wires (black) on the lights and bilge pump go to the black wire coming from the negative side of the battery correct? And this is where you hooked up the black wire from the 520? The red wire from the battery is positive and that feeds all the accessories (at the fuse panel) including the 520, right? Just wanted to make sure there wasn't a reverse polarity issue, that when the guy did it himself he didn't do something backwards.

[Bigtom]

Scott,I strongly agree with Leech. I had the same problem with my LCX-27. I took the time (about 4 hours) to run a new power wire and negitive. Having to remove over 6 panels off my crestliner it was worth the time and a few beers, also a bigger guage old extension cord works great for wire.