Can anyone help me figure out the color of the wire I should be looking for under the dash? I think it may be orange, but not sure. Also on a 73 I would think it runs under the mat (or carpet) back to the inside of cab tank. Can anyone help me out on this? Maybe 73 and 74 is the same? I am guessing it would just be a single wire for the fuel tank sending unit. Does anyone have an extra that they would sell if I can't find mine? It appears to be missing (unplugged).

 

first of all, in-cab tank or from the bed?
if from the bed-- I'm not sure
if in-cab-- Mine was orange, and ran from a rubber bung through the rear cab pillar on the DS up and over the door down into the space behind the dash. I only have one tank so the wire plugged into an black rubber 2 position boot with one Orange lead exiting and one orange lead doubled back into itself (I'll try to find you a photo).

According to a wiring diagram I found on the fordification site if you have dual tanks it would plug into a harness that goes to the switch, which would have the female end of the dual position boot, and the second wire would then plug into the second position in the dual tank wiring.

The orange wire under the dash goes from the dual position boot into the wiring harness and into the instrument cluster plug.

 

I did state "inside of cab tank" in my above post. Thanks for any help! yeah, I see a double plug type of deal under the dash. A pic would really help me out a lot. No dual tanks....single in cab tank only, here! Thanks

 

Its a bit hard to tell, but the wire out of it is Orange and there is an orange wire looped (Jumped) from one plug to the other inside the rubber housing

Not sure why the photo won't show?!

 

NOT the one my finger is holding up, the one the orange sending unit wire end is resting on. I couldn't add the labeled photo for some reason, sorry

 

Take the rubber oval that you think it goes to and connect a jumper wire to it. Plug the dash back in and turn the key on. Watch the gauge and ground the other end of the jumper. If the gauge moves to full then that is where it connects.

 

Will I need to pull my dash cluster out to find this looped plug? I guess I thought I could just look under my dash and spot it.

 

couldn't say. Mine was all torn down for repair anyway.

 

It plugs into the yellow plug where your right index finger is holding up the green wire. Should be a three plug pigtail.

 

You can go to 1973-1979 Ford Truck Wiring Diagrams & Schematics - FORDification.net .There you will find the complete FACTORY wiring diagrams for a '74. They're working on the '73 but don't have it yet. Should be the same though.

 

2x And I stole this from another thread:



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thanks for all the help guys! Now I need to find one of those wires at a decent price. Used would be fine. Anyone have any ideas? Already checked eBay.

 

That 3-connector pigtail is NOT for a fuel gauge. That's a 12-volt accessory tap, and the ORANGE wire shown looks like power to the heater controls. Wiring to and from the fuel gauge is contained completely in the instrument cluster connector harness. It does not even pass through the fuse panel.

Solid 12-volt power does NOT go to the fuel gauge circuit at all. A BLACK with GREEN stripe resistance wire (8 to 9 ohms) goes to the instrument cluster. This powers the ICVR that in turn powers the fuel gauge. The ground sense of the fuel gauge goes out to the sending unit (assuming single tank) through what should be an ORANGE wire (NOT what is shown in the pic) contained in the instrument panel connector.

I can't find a diagram for a '73, so the color of the sending unit wire I mentioned could be innacurate. However, the scheme I have described is true of almost ALL older-model Fords. There is never a case where a fuel gauge taps off a keyed accessory tap like what is shown in the picture. It is always powered through an unfused resistance wire that runs to the cluster connector.

 

Disregard what I mentioned before. If you need to know where the fuel gauge sending unit wire connects let me know and I'll provide a picture of the CORRECT connector. The yellow pigtail I showed was the INCORRECT location.

 

I believe the orange wire going to the yellow connector is the power to the fuel selector solenoid switch on the heater control panel.



It is very hard to tell from the wiring diagrams and the only reference I can find to the 3 hole yellow connector is to 13A705 in the pic below.

click to enlarge.

Sorry for my misleading info in the previous post. The Orange wire is NOT the signal wire as fmc400 correctly pointed out.

fmc400: Anyway to verify this? My dash isn't out at the current time and my wiring is for a rear and mid-ship tank.

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