Have a Motor Guide 46Lb Thrust 12V. We were on an electric only lake tonight and the TM died about 10 minutes out. We only would've had an hour fishing time till dark so I checked the obvious connections while we made our way back to the dock and then headed home so I'd still have some light to check everything with a multitester.

Wasn't getting any juice up to the front plug. A fuse near the battery was blown. It was a 32V AGC 30 Buss fuse that was blown. That didn't seem right so I checked the manual and it says it should have a 50Amp Circuit breaker at that location. Of course MotorGuide gives a part number to order one from them.

Shouldn't there be something I can pickup at RadioShack or WalMart that'll give me the same protection?

I'm sure I yanked some wires cleaning the back compartment and installing battery boxes yesterday, so I just have to find the short. The TM worked fine when I tested it outside the boat later on.

After reading your post again, not sure about the fuse. Was this fuse in line with the TM cables or the power cables feeding the accessories? Don't sound like it was connected to the TM if you said the TM worked when you got it home, so it sounds like the accessory fuse and you may have done something to blow it.  If it was connected to the TM cable, that's no where near enough fuse and it probably just blew for too much current running the TM

Also if that was the accessory fuse, you need to check to make sure there is no circuit breaker, looks like a small square block connected to one of the battery terminals. Auto reset breakers will reset after the cool down. It may have one and just too small. Another possibility is a bad connection, it takes a lot more current to run the motor under a load than out of the water. A bad connection will show up when loaded while the motor will run just fine out of the water. Could also be a bad motor.

Almost any boat dealer should have the circuit breaker.

If it was me I would get the 50 amp breaker. Any boat dealer should have one.

The other day I posted how the boat had the batteries reversed when I got it. Deep cycle was to starter and accessories and TM was connected to the Starting battery.

I'll have to check tomorrow , but I wouldn't be surprised if that fuse wasn't meant for the starter/accessories battery.  Maybe, the correct TM Circuit Breaker is on the other battery line. I have to call the previous owner and ask about the radio antenna that he forgot to give me. I suspect when his son and him got newer boats they swapped batteries and got them reversed.

I've wanted to inspect all the wiring this winter, but maybe I better start now.

You'll have a tough time finding a breaker replacement that size at Wally world or Radio shack.  Try BPS or Cabela's.

Looks like I need to check for one of these. Cabela's  $6, although I'll trace the wiring today and see if one isn't already in there somewhere, possibly on the wrong set of wires.

It will have two lugs coming out the bottom like that but won't have the mounting tabs, may be in a plastic case also.  One lug should have a connecting strap on it and bolted directly to the battery and the TM cable bolted to the other lug

You should only have the large TM cables connected to the deep cycle TM battery, there should be no other wires going to it.  All accessories and everything else should be connnected to the cranking battery.

Usually the only two big cables connected to the cranking battery are the battery leads going to the motor and if like most others, one #10 - #12 wire with a inline fuse going to a fuse/breaker panel or main power switch and some smaller wires going to who knows what.

Way2slow,question on your comment nothing should be connected to the trolling

motor but itself,if you only have one battery and a tiller manual start motor where do you hook the depth finder positive, negative too then?Buy another battery for the depthfinder?Mines hooked to the trolling motor battery,don't think

it draws enought to make a difference. :-?

It's not recommended to run your depth finder or any electronics off the TM battery. You're variable speed TM's are operated by a high frequency square-wave signal that the on/off times is what controls the motor speed. This creates the posibility for the signal to feed back into the electronics and damage them. Even though there are suppose be built in filters to prevent this, is still can happen. With the non-varialbe speed, the ones with the 5 or 6 switch positons for speed, you have constant voltage spikes generated everytime you press the foot switch, these can damage your electonics. Again, there are filters built in to prevent this but if your's is one in the thousand that gets damaged, still don't help you much.

On my jon boat where I'm only using one TM battery and no cranking battery, I just use a small $20 lawn mower battery to run the depth finder when I'm using one in it. It doesn't take much battery to run one the whole day, even the whole week as far as that goes.

Yes, you can run everything off one battery, bunches of people do it but it can come back and bite you in the butt. When it does, you loose.

Forgot to mention, these can also damage the electronics in a lot of you new outboards, which can get very expensive.

Ordered the breaker from Cabela's. I was hoping to find something local, but even the Boat shop about 20 miles down the road only had 50A fuses for TM's. The only place I forgot to call was Dick's Sporting Goods.

The only thing wired to the Deep Cycle battery besides the TM is the console battery gauge.