Wiring to Fuel Main/Aux panel switch on helm

MrD

MrD

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Can someone please explain to me what I am doing wrong? I bought a on-off-on rocker switch, double pole double throw to replace the old Grady White Main/Aux Fuel switch. Am I connecting these wires correctly to the back of the switch? Thanks for any help.
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The finished product looks like this:
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Wiring looks reasonable to me.

Back up a bit. Why are you changing the switch? Is this how the original switch was wired?

Are your sending units good? What readings where they giving before?
 
Do you have a better picture on the wiring diagram for the new switch. Its very faint and hard to see. I think you have the ground in the wrong place. But I cant see it very well.
 
Can you post the switch make and model number?
 
Your schematic seems to show up well - Chelsea, it must be on your end?

But, yes, please post a pinout for your particular gauge.

Also, as mentioned, did you trouble shoot the problem before replacing it? Verified that both senders (and feed/ground wires) are good?
 
If that positive feed somehow connected to the sender lead, I am sure the senders are toast. That is why a diagram of the switch pinning is important.
 
I think I found the switch on amazon. The #5 terminal is your issue, I think. Are you using that to supply voltage to the sending units in the tanks?? I'm confused by your description, "fuel gauge on the dash sender" #2 is power in for the lights on the switch.
 
Hookup1 said:
Wiring looks reasonable to me.

Back up a bit. Why are you changing the switch? Is this how the original switch was wired?

Are your sending units good? What readings where they giving before?
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Hookup1, yes,sending units and gauge functioning when I wire them directly. The original was wired similary except it was a toggle switch and now I am upgrading the whole panel to rocker switches.
 

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Chessie246G said:
I think I found the switch on amazon. The #5 terminal is your issue, I think. Are you using that to supply voltage to the sending units in the tanks?? I'm confused by your description, "fuel gauge on the dash sender" #2 is power in for the lights on the switch.
Click to expand...
"fuel gauge on the dash sender" is the terminal on the fuel gauge for the sender wire. I have 2 senders, from 2 tanks, these both come to the switch, this is where I am confused, how do I send the signal to the fuel guage from the sender?

Also, thank you all for the questions and help. I updated the old panel as many of the switches and fuses were busted. Both tanks senders were working with the old style toggle switch. It is just with this new style of switch that I can't figure out how to send a feed from the senders to the guage.
 
MrD said:
"fuel gauge on the dash sender" is the terminal on the fuel gauge for the sender wire. I have 2 senders, from 2 tanks, these both come to the switch, this is where I am confused, how do I send the signal to the fuel guage from the sender?

Also, thank you all for the questions and help. I updated the old panel as many of the switches and fuses were busted. Both tanks senders were working with the old style toggle switch. It is just with this new style of switch that I can't figure out how to send a feed from the senders to the guage.
Click to expand...
I think the confusing part was the "sender" on the dash. The senders are the pieces in the tank... a sender "sends" information.

Toggle vs rocker makes no difference.

You should only need one "sender" wire going to your fuel gauge. You switch receives the two individual signals from the individual sender and then you select (via the rocker switch selection) which signal continues to the fuel gauge.
 
Ok, First you have momentary switch. Meaning its only going to work when the button is pushed, once you let it go your gauge will read empty.

Terminal #5 is your issue... for sure. jump it to terminal #2. Input from forward tank terminal #4, aft tank #6. Jump #1and #3 and they go to the gauge. You're turning 2 inputs into 1 output, controlling which input signal via the switch. The only issue I see is the momentary switch.


I may be wrong. I think #5 need to jump to ground (#7)


That wiring diagram is about as clear as mud!!!
 
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So if Chessie246G is right you have the wrong switch but it should show proper levels if you hold it down. But it doesn't look like a momentary switch to me.

On a DPDT switch the center connection is switched to the one above it and the one below it. Since this is double pole you have two independent switches. Since this switch is lighted you need to supply + and - 12VDC to the switch. For now forget about the light. Use the side of the switch with no connections to the lights otherwise you will get bad fuel level information. If you are not sure put a ohm meter on it.

You should disconnect the light wires and see if you can get the fuel level working

Your diagram pins 4, 5 and 6 are all you need to switch the sending units to the fuel gauge. Verify that 5 pink wire does go to the fuel gauge.

The sending units are grounded at the tank and the other side comes up to the switch panel as pink and pink/white. They should be on pins 4 and 6.

The purple wire should have +12 VDC when the ignition switch is turned "ON". At this point you should have a fuel gauge that shows some "life", correct fuel levels and the switch working. Turn ignition off, flip fuel tank switch and turn ignition on - speeds up tank level sensing.

If fuel levels are properly indicated you can decide how the lights in the switch should work.
 
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I didn't see in the amazon where it says the switch is momentary. In fact, in the Q&A section, someone asks if it is momentary and the reply was No.
According to you original diagram and the diagram in the Amazon link, the wiring on the right back side of the switch should be correct. I don't know what the sketched in line on the upper left is. It says jumper to fuel gauge purple.
Other than the 12+v connected on the left side to terminal 2 do not connect anything to terminals 1 and 3. If the 12v is correct and the ground is good (top right) when the switch is activated one of the leds on the face should light.

To test the wiring for the senders, first ground the pink wire. The dash gauge should read full. Remove the pink wire and the gauge should read empty.
Now connect (touch) the pink wire to one of the two sender signals and the gauge should read some level depending on how full the tank is. If that works, re-touch the pink wire to the other sender wire and the same thing should happen.
Now reconnect the three wires as shown and the tanks levels should work correctly. If not, the center lug on the right side may not be the common lug although it looks like it is on the amazon description.

You can use an ohmeter to test the function of the switch.
All that said, is it possible that the sender signals didn't work before and you thought the switch was bad?
 
Mr. D - I don't know what year your boat is but that fake woodgrain panel look identical to my 1997. Mine does not have lighted switches (nightlights when running lights are on). The lights in my switches indicate "ON" like a bait well or bilge pump. The light makes no sense for a fuel switch that indicates "Main" or "Aux". Don't bother to hook the light in the switch up.

I reworked my bilge switches to have a tiny LED wide-angle light if my pump is running. This is highly recommended as a safety item. I found that you can't see the lights imbedded in the switches especially if they are LED.

If you are replacing all the switches with lighted ones you can connect them all together and wire to the running lights. That way at night all the switches will be lit. It the same as how your gauges are wired.
 
MrD did not really describe what trouble he is seeing.
MrD did not show us the gauge connections.
I suspect that the gauge is still connected to the key switch and accessory lighting.

I am assuming we are talking about an analog gauge.

Often OEM analog fuel gauges are wired with the purple wire to the Ignition switch Accessory power. (the key turns it ON)
In that case the gauge is always powered when the key is on and is not powered with the key off. The gauge was usually lit also, either with all the other gauges or by use of a jumper on the gauge.
Some single tank setups used a momentary switch to view the gauge. That way it was not drawing power all day.
(I hated that setup because you had to hold the switch to see the level while you were pumping gas...)

Dual tank setups used a switch to choose which tank was reading.
The best setup is to disconnect power from the Ignition switch entirely, including the gauge light. The OPs diagram looks right so long as that was done.( disconnect the purple wire)
Pins 4,5,6 are choosing the tank to read.
The jumper across 1 & 3 will provide power to the gauge when either tank is chosen but not when the switch is off. You must not still have power coming from the key switch or it will power the gauge regardless of your switch.
A quirk to this setup is that both switch lights will light in either of the ON positions(because of the jumper)
This setup allows you to turn OFF the gauge. Thats good.

I would light the gauge with the Gauge + jumpered to the gauge light power.
 
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SkunkBoat said:
MrD did not really describe what trouble he is seeing.
MrD did not show us the gauge connections.
I suspect that the gauge is still connected to the key switch and accessory lighting.

I am assuming we are talking about an analog gauge.

Often OEM analog fuel gauges are wired with the purple wire to the Ignition switch Accessory power. (the key turns it ON)
In that case the gauge is always powered when the key is on and is not powered with the key off. The gauge was usually lit also, either with all the other gauges or by use of a jumper on the gauge.
Some single tank setups used a momentary switch to view the gauge. That way it was not drawing power all day.
(I hated that setup because you had to hold the switch to see the level while you were pumping gas...)

Dual tank setups used a switch to choose which tank was reading.
The best setup is to disconnect power from the Ignition switch entirely, including the gauge light. The OPs diagram looks right so long as that was done.( disconnect the purple wire)
Pins 4,5,6 are choosing the tank to read.
The jumper across 1 & 3 will provide power to the gauge when either tank is chosen but not when the switch is off. You must not still have power coming from the key switch or it will power the gauge regardless of your switch.
A quirk to this setup is that both switch lights will light in either of the ON positions(because of the jumper)
This setup allows you to turn OFF the gauge. Thats good.

I would light the gauge with the Gauge + jumpered to the gauge light power.
Click to expand...
Thank you all for your help. I believe I can now figure this out. I am going to use Pins 1,2,3 to run power up to the gauge, and pins 4,5,6 for the tank sending wires and 1 wire to sending input of gauge.

Yes, gauge is analog.
Trouble was I did not try this configuration thus was not getting a signal sent to the gauge.

As Hookup1 says "Your diagram pins 4, 5 and 6 are all you need to switch the sending units to the fuel gauge. Verify that 5 pink wire does go to the fuel gauge." I now understand that the toggle switch really doesn't even need power, I am using the 2nd pole pins 4,5,6 to switch between Aux fuel tank and main fuel tank. This is what I was confused about. Pole 1, pins 1,2,3 will run power to the gauge.

I will be working on the boat later tonight and will report back.
 
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