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Which wire goes to which terminal on the back of the gauges? Or does it not matter?
On the back of my custom cab with sweep speedo gauge cluster, the temp and fuel gauges have two posts, but neither have any factory markings. It appears a PO wrote with sharpie a “+” and “I” next to each post on each gauge, but that is confusing to me because I would assume that “I” means ignition and that “+” means 12v (same thing in my mind), so then which would be the hot and which would be the sending unit? I’ve seen gauges in the past with a post labeled “S” for sending unit, so something tells me that it does matter and that you can’t just hook them up to either terminal.
I have the factory wiring diagrams, but that doesn’t really help because all of the original wiring is gone, so the color of factory wires means nothing at this point.
im using an EZ wiring 12 kit, if that makes a difference
So my question is, looking at the back of the gauge cluster, which post gets power, and which post goes to the sender?
Looks like probably + (positive) and - (negative) signs not an I
Doh! Okay well if that’s the case, then the assumption would be that looking at the panel from the rear, the left hand terminal on both the temp and fuel gauge connects to the sending unit, and the right hand gets power?
if this assumption is wrong, what’s the worse that will happen if I hook the gauges up backwards?
and also just to confirm, I’m pulling gauge power off the side of the voltage regulator that doesn’t say IGN, right?
Based on Becky is a 66's picture and comparing it to mine I would have to say it must not matter which terminal the wires go on as they are opposite. I can only say mine worked before I took it out.
Thanks guys! Can anyone confirm that it does not matter which post is connected to the sending unit and which post connects to gauge power? I just want to be sure, I don’t want to burn out my gauges! Thanks!
So does it matter which terminal you connect the sender wire or the power wire to the back of the temp and fuel gauges on a custom cab?
There’s no harm if the wires are reversed?
I looked on Fordification's site at wiring diagrams. Their diagrams start at 1967, however the diagram does show where which wire goes on the gauge. I'd imagine the diagram for your year would also show this.
I did not read every word in this thread but all the gauges get power from the IVR to the low side of the gauge. IE. "empty", "cold", "0 psi", the other side goes to the senders. The gauges are just measuring current flow to ground.
I did not read every word in this thread but all the gauges get power from the IVR to the low side of the gauge. IE. "empty", "cold", "0 psi", the other side goes to the senders. The gauges are just measuring current flow to ground.
So just to confirm, when looking at the back of the gauge cluster, the post on the right hand side of the fuel and temp gauges goes to IVR power, and the left hand side goes to the sending unit?
I just went back and looked through all my notes and schematics from my dash rewire....nothing definitive except....BK/GRN from IVCR is the reduced power source to the gauges. Since you have no wire colors to go by, I would attach IVCR feed to where PO had marked + on the backs....I don't think it will damage the gauges with the wires reversed. I seem to remember my fuel gauge bottoming out backwards while I was hooking mine up...reversed the wires and needle moved in the correct direction.
