Voltage drop at voltmeter, ignition on

[foilled]

so i have having a voltage drop at the voltmeter with the key in run position. Gauge is measuring correctly but while looking for the issues which has been narrowed down to the positive side I saw the connection to my nav lights looking questionable. What’s broken here and why does nav light still work? Switch goes both way except only one way turns red green and white light on. Here’s a photo you can see the white wire burnt. The wires don’t seem to have wires going threw it but a white tube with a super small battery in it were it looks like it burnt in photo. Any help?

 

[foilled]

[No message]

 

[Scott Danforth]

the wiring is fuggly, however you can see the other end of the broken wire in the pic.

however for the voltage drop, look between the battery and the ignition switch at every connection. clean them, and then seal them. the light is further down the path, while the dash battery gauge is connected to the ignition switch.

 

[foilled]

the wiring is fuggly, however you can see the other end of the broken wire in the pic.

however for the voltage drop, look between the battery and the ignition switch at every connection. clean them, and then seal them. the light is further down the path, while the dash battery gauge is connected to the ignition switch.

Battery voltage fresh off charger is 13 volts. At the hot wire going to ignition I’m at 13.8 with ignition off. With ignition on the purple wire coming off is 12.8 volts. Wouldn’t the drop off be after ignition somewhere from resistances in a gauge or accessory switch? I’m still having voltage drop at voltmeter. My voltmeter must Not be connected directly to ignition?

 

[Scott Danforth]

you cant have a higher voltage at the ignition than your battery is putting out so if you have 13.0 volts at the battery, your 13.8 volts is incorrect.

if you have 13.8 volts going into the switch and 12.8 coming out, your switch is shot. if your voltage drops from 13.8 to 12.8, either your battery is weak, or you have a bad connection somewhere. the other choice is a 25 amp load on your ignition circuit (20' of 10 gauge wire)

your volt meter is a suggestion as it cost the boat manufacturer about $3 for the gauge. they are not known to be accurate

 

[foilled]

you cant have a higher voltage at the ignition than your battery is putting out so if you have 13.0 volts at the battery, your 13.8 volts is incorrect.

if you have 13.8 volts going into the switch and 12.8 coming out, your switch is shot. if your voltage drops from 13.8 to 12.8, either your battery is weak, or you have a bad connection somewhere. the other choice is a 25 amp load on your ignition circuit (20' of 10 gauge wire)

your volt meter is a suggestion as it cost the boat manufacturer about $3 for the gauge. they are not known to be accurate

Yes ignition reads higher then battery? Just replace? And I’ve been using the multi meter on positive and negative nutshell behind voltmeter and they match so I no it works. And yes it’s dropping from ignition hot wire to purple exit wires by about 1 volt when ignition is turned to run

 

[Scott Danforth]

you cant have a higher voltage at your ignition than you have at the battery. if you do, clone your ignition switch as it is generating power via magic.

verify the battery voltage, then verify the voltage at the main engine connector, then verify the voltage at the ignition switch. they all should be exactly the same, or at least within 0.01 volt

 

[foilled]

you cant have a higher voltage at your ignition than you have at the battery. if you do, clone your ignition switch as it is generating power via magic.

verify the battery voltage, then verify the voltage at the main engine connector, then verify the voltage at the ignition switch. they all should be exactly the same, or at least within 0.01 volt

Just remeasured 12.75 volts at battery. I have 3 positive wires going to ignition they actually all measure 12.75 too. When i turn ignition to run it drops to 12.02. Also with ignition in run I get 11.78 at purple wires

 

[foilled]

The voltmeter is the same voltage as the purple wires. Is it dropping to low and why. I must have resistance in system. If I hook up battery positive to gauge positive I have .7 to an 1 volts or so, while Negative to negative is basically 0.

 

[Scott Danforth]

any voltage drop in the wire is a bad connection. start at the batteries and clean every connection (positive and ground) to the motor/block, then thru the harness to the switch and ground buss. there are 3 harness connections alone, not to mention the starter B terminal and the 90 amp fuse as well as the block connection and the batt connections

 

[foilled]

any voltage drop in the wire is a bad connection. start at the batteries and clean every connection (positive and ground) to the motor/block, then thru the harness to the switch and ground buss. there are 3 harness connections alone, not to mention the starter B terminal and the 90 amp fuse as well as the block connection and the batt connections

The issues is definitely before the ignition even though the drop is after it? How do I go about cleaning wire harness and do I do anything with the 90 amp fuse?

 

[Scott Danforth]

you take a scotchbright pad, take the connections apart, clean them to shiny metal (clean enough your wife would eat off of it), then you put the connection back together. when done you seal the connections with marine electrical varnish.

 

[foilled]

you take a scotchbright pad, take the connections apart, clean them to shiny metal (clean enough your wife would eat off of it), then you put the connection back together. when done you seal the connections with marine electrical varnish.

Sounds good. Is there’s a way to see specifically which side of the ignition switch the resistance is coming from?

 

[Redrig]

is it possible that the points are just closed and creating the drop ?

 

[Scott Danforth]

is it possible that the points are just closed and creating the drop ?

a 1 volt drop on a system without a bad connection in the circuit would be a 25 amp draw. you would see smoke if the points or any part of the ignition was drawing 25 amps

 

[Redrig]

makes sense , just a thought