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I seem to have a short somewhere in my boat. The cranking battery runs down when not in use over 2-3 days. all my electronic and pumps and everything else except my trolling motor is connected to it. I have determined that is the electronics by testing the fuses with a test light. All the electronics are connected to a fused circiut board under the dash. How do i test the board? any ideas? When the electronics are unconnected it still shows a short with a test light at the fuse block.
Have you load tested your battery? How did you determine it was the electronics with a test light?
I'd say if you have a test meter you could set it to mil amps and check it for draw at the fuses. You'll need to remove the fuses to do it. There may be a small amount of draw even with the units off, the culprit should show a big difference though. Another way would be to remove the fuses one at a time until your battery stops going down.
I removed all the wires from the positive post and attached a test light between the post and the led the test light showed current and then i removed the fuses one at time untill the test light went off. It went off when i pulled the fuse to the electronics.Quote:
Originally Posted by justinp61
tried to test load battery and it was not charged up enough, will try again later. Still it should not show current when everything is turned off? Right?
The way you did it is correct. Sounds like electronics. Try unplugging the power cord from the head unit and put the fuse back in and check again..If test light still lights up its in the cord.
Is by chance this Lowrance with SS and you have the yellow wire on a switch? and forgot to turn off?
I'm not following what you did. The light will show voltage, you'll need a meter to show amp draw. It sounds almost like you have something back feeding.Quote:
Originally Posted by REDEYE50
Justin, He took the wires off the batt. pos. terminal and hooked to one end on the test light. he hooked the other end of test light to bat. post. The light lit up which means there is current going through. when he pulled the fuse for the electronics the light went out. That's the best way there is to check for a current draw.
I see said the blind man.
Are there multiple electronics on that one fuse?
You on the right track. It takes the lamps specified voltage range and current to turn the lamp on (visibility). Ohms Law. I = E/R
Install a battery switch.
how old is the battery, and if you dont have a onboard charger get one and plug it in all the time
A battery switch would only mask the problem. You have an undesirable current drain that needs to be isolated and fixed.
If I remember right(?) if its a LOW unit and u have a stand a lone GPS antenna that antenna is always pulling some power unless u have a separate switch to turn off its power in the NMEA 2k wiring. This switch would be placed between the power source and the fuse , that being before the power line is plugged into the NMEA 2k system. The GPs antenna does not get its power from the screen unit.
These are brand new Humminbird units but this was happening before install of new units. Both units are plugged into circuit boards(one under the dash & one under the bow). When the units are unplugged the test light still works until the fuse is pulled. Meaning the units have nothing to do with the problem, so it's got to be the circuit board? Right? I know a 4 bank charger would keep all 3 trolling batteries and the cranking battery charged but I would like to fix the problem if I can.
The cranking battery is a Blue Top Marine Dual purpose AGM 800 CCA. This battery has been complety dead about 3 times over the last 6 months but has always been recharged back. I have left a 10 amp charger on it over night just to make sure it is up. It will last about 1 1/2 days and then battery is about dead. won't crank, trim will not work locators will not work. During a day of fishing in the late afternoon when I start the the engine the locators will shut down telling me that the battery is low. Charge it up that night and it will run about 1 1/2 days. Need to find the problem. Even if the battery is getting old I still have a short. Thanks
Your battery needs to be load tested. If you have another battery try and see if it performs better. Humminbird electronics will only have a 3 amp draw.
Okay, Your power cord to each Humminbird is connected to a circuit board. What exactly are these circuit boards, are they basically just a terminal strip with no fuses? Where is this fuse you pull and the draw stops? On my boat, there is a fuse panel/circuit board under the dash. There are terminals to hook up equipment and each one is fused. If you have a terminal strip under the dash or thereabouts which 1 H/B is hooked to, and another terminal strip on the bow that the other H/B is hooked to, you need to start a process of elimination. Find out where the bow terminal strip is getting it's power. Disconnect that and see if you are still getting a draw. If so, look to the terminal strip for the console H/B and disconnect the power to it. Do you happen to have a radio on the boat? Some of those have a constant power draw.
[QUOTE=Shellback;2638537]Okay, . Do you happen to have a radio on the boat? Some of those have a constant power draw.[/QUOTE
Good thinkin, or even a clock will draw. Sometimes a certain battery charger when hooked up will draw a little when not plugged in to AC. How bright is the test light? Very dim or fully lit?
You said "i removed the fuses one at time untill the test light went off". What ever fuse you pulled that caused the light to go off is where the problem is.
"All the electronics are connected to a fused circiut board under the dash. "
" It went off when i pulled the fuse to the electronics."
"Both units are plugged into circuit boards(one under the dash & one under the bow)."
" When the units are unplugged the test light still works until the fuse is pulled"
Trying to understand if the electronics are connected directly to the fuse panel, or as you stated, " a circuit board under the dash and one on the bow"?
Get a couple of pictures of the elec panels would help a bunch. Put us all on the same page. What about switches? My boat has/had a power switch and accessory switch.
Personally, I would disconnect the electronics wires one at a time until I isolated the problem.
I would load test battery before doing anything else. When trouble shooting any electrical problem it is important to eliminate the easiest fixes first.
What you have is not a short. A short blows fuses. If wires are not fused it melts and burns wire. As others have stated you have an unintended power drain or a weak battery.
If you like to T/S and fix your own electrical problems. If do not have one get a good multi meter. Spend somewhere betwixt 60-100 for a decent one.
Next remove battery from system and fully re-charge. I usually let mine set overnight . After done charging measure voltage across terminals it should read somewhere between 13.5 and 14 volts. If it does this is a good sign as far as re-charging. Now can it hold a charge. The way I check is I made a load of two headlights hooked in parallel with two alligator clips that fit on battery terminals. This will put a decent load on battery. With lights on wait about 10 minutes and then measure voltage again. Should still measure well above 12 volts if below 12 battery needs replaced. If that test passes re-install battery but hook up ONLY your primary ignition wire for your boats engine. Place your multi meter lead on battery again and turn engine starter. Make sure fuel is shut off or disconnected as you don't want an accidental start. If voltage falls below 12 rather quickly chances are battery is going bad. We are talking like 5 second here. The greatest amp draw on your battery is when you start it. Another clue a typical lead cell acid battery life is about 5 years. Poor maintenance practice or poorly constructed of course can greatly affect that
If your battery passes all these test then and only then would I start trying to figure out a power drain. I just can't imagine any electronics dragging a good battery down over such a short time.
Do what Canepole said "Personally, I would disconnect the electronics wires one at a time until I isolated the problem." If that doesn't work check your motors charging system. Your rectifier has 4 or 6 diodes in it. If the right one shorts it can cause that exact same problem.
Well I guess I will just save what time I invested in trying to help. My advice if it was
was sound or not was just deemed worthless.
My fault for forgetting that no good deed ever goes unpunished. I won't make that mistake in
this forum again.
Mr Moderator the floor is all yours once again.
thanks for the help. I just have not had time to further explore the problem. I just pulled the fuse until i get time to work on it. Thanks again will let everyone know how it turns outQuote:
Originally Posted by hays47
Your advice certainly isn't worthless. The battery should be the first thing checked with any electrical problem.Quote:
Originally Posted by hays47
Power first always. What was described (as I interpreted it) was an undesirable current drain. Isolate and eradicate.
:biggrinUPDATE! I had the battery load tested and it tested good. I then removed the fuse panel and checked for loose wires or connections. NONE. I then went to the circiut board that was labeled "Electronic only" which is a plastic board with 2 rows of spade connections. All seemed tight and no corrossion. I then dissconnected the + side of the battery and connected the test light between the + post and the led wire going to the fuse panel. Before there was a dim light in the test light showing a draw. THIS TIME THERE WAS NOT! Tried it several times, tested light to make sure it was working, No Draw. All I can say is " the ELECTRIC GODS must have fixed it". We will see. Thanks for all the advice it was greatly appreciated.
If you (Redeye) did nothing to fix it, the EIR Gods will give the current drain back at a most undesirable or unwanted time.
Yep Thats what I am afraid of!! LOL going to keep an eye on it for awhile. Thanks again to all.Quote:
Originally Posted by Cane Pole