My HB's both read around 1 volt low when fishing. I check the voltage at battery and see 12.8 then the load side of the main power switch once turned on shows 1 volt less. There is a relay in the wire bundle behind the switch that gets hot to the touch. I have both birds unplugged and still see this drop. All of the switches have an indicator light that is always on when main is on. Could the small bulbs in the switches be pulling that much current to make the relay very hot? With nothing else on I see this problem. Any ideas? Thanks

for one your wiring alone can cause a voltage drop, resistance is more in smaller wires and length matters too.

my birds (688 in dash, 998 on dash, 898 bow) all show low voltage warnings when fishing but it is not a problem. you can also set the voltage warning in the menu so that 3-4 volts are what set it off.

it could also be from starting, the birds will show low voltage due to the huge amp load to turn the engine over.

as for a hot resistor? how hot, burn the finger in a flash hot or can you put your finger on it for a min or more?

not familiar with your wiring layout so not sure about resistor but unlikely they needed one in your control panel. if it is getting really hot then pull the panel and look very closely for bare wire/shorts, loose connections at switches (this causes heat real quick) or anything in general that is not right.

It is a relay not a resistor. I can hold it but its too hot to just be in the on position and nothing running. Could a relay like this be bad/ I cannot find where the draw is yet. I plan to pull wires on each switch one at a time. Some of the switches have diodes on them?

a relay can get hot but should just be "pretty warm" not burn the fingers hot.

how many poles on it? most time you can pick them up at the vato zone parts house to replace.



diodes should not be causing any extra heat, they just keep the backfeed from happening.
definition.
The most common function of a diode is to allow an electric current to pass in one direction (called the diode's forward direction), while blocking current in the opposite direction (the reverse direction). Thus, the diode can be viewed as an electronic version of a check valve.


if the relay is hot I would unhook the feed side (to switch) and hook something simple up so that the relay will activate. a light bulb etc. so you don't have a lot of amp draw, hold it and see if it heats up again, if so you know the load side is bad, if not then you know the switch side is bad and can start your search.

if the space is too cramped and you can remove the relay then a battery charger set at 10 amps can be used to test or another battery. I keep test leads made up to do this stuff, saves a bunch of money when stuff breaks.

I will do each switch individual and put a dvm on amps in line to see the draw. What kind of bulbs are in the switches? If they were LEDS it would help but I doubt it as 2003 tech was not there yet.

A relay should not get hot in my opinion, as it is just a switch and presents no load, so no power is consumed to create the heat.

If the relay is hot, there is a problem. Most likely you have an overload condition on the load side of the relay which results in burnt contacts, creating resistance and a load as power is consumed to overcome the burnt contacts.

Disco wires as planned to find and fix the load. Replace the relay with the same type, but bigger if available. Good luck.

Why does your FF power go through a relay. It should be connected directly to the power souce and protected by a fuse. It's OK to switch power off at a switch as long as you allow the FF to power down on it's own.

The FF powers it self thru an ACC switch on the dash and what I can tell is the main power switch activates this relay tied to the main bundle. It looks factory from Triton. I do not understand the need for this relay either.

If you are electronics heavy, the load will over come your ignition switch and burn it out. A relay will isolate the load from the ignition switch.

Check the main breaker. Have been seeing some not having the correct voltage on the out side. Plays havoc with touch switch`s but I can see this effecting consol voltage. Looks like this:

Relays can get hot since it has a series of coils inside designed to become an electomagnet when energized and hold the relay in. A relay is usually there to connect heavy current when a simple toggle is not heavy enough to handle the load. The Toggle will energize the relay, then a connection will be made like a switch. With the relay activated, there is current going through the coils to keep the relay activated. Don't know if it would result in a 1VDC drop or not. I would first trace the wireing to see what the relay is connecting.
John

Correct. There is a coil of very fine copper wire inside the relay that pulls the contacts together. The very fine copper wire pulls a very small current, so it could warm up a bit, but I've never experienced a hot relay caused by coil current heat.

This could be ambient heat maybe.

The relay is hot in as boat is in an insulated barn and when no power is on its cool. I have tried 2 calibrated DVM's and the one on battery stays at 12.8 and the incoming side of relay when master is on is 12.2 and the load side shows 11.2vdc while the battery stays at 12.8. This one really confuses me. I have not removed the resettable fuse panel yet, that is my next exploratory surgery. I do not have one of those main breakers that I can see, it may be hidden?

stays at 12.8 and the incoming side of relay when master is on is 12.2 and the load side shows 11.2vdc while the battery stays at 12.8 "Tells me the relay is bad" only 11.2 coming out of relay.

Ok what kind of relay is that? Looks like a double pole double throw maybe. Should be simple to find right?