Fuel tank to Gauge wiring

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tadslc

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Having a terrible time tracking down a potential wiring issue with my gas gauge / sender.

I have the manual but just can't seem to read the diagrams very well.

I found the gauge in the wiring diagram and see the 3 contacts but can't figure out were it goes from there.

No tach but do have Oil, Temp and Voltage.

Can anyone supply me with a readable diagram.
 

consti2tion

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Found these on another forum. Looks like you're looking for a Tan wire with a White stripe. The harness comes out of the bulkhead connector and runs down the drivers side frame rail with your tail light harness.
 

GTX63

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I found the gauge in the wiring diagram and see the 3 contacts but can't figure out were it goes from there.

No tach but do have Oil, Temp and Voltage.

Can anyone supply me with a readable diagram.

No diagram but I can give you the layman's version.

Fuel gauge issues are either
A bad gauge
A bad sending unit
A broken wire/ground or failing circuit board

Attached to the back of the fuel gauge are three male terminals. 3, 6 and 9 o'clock.
The 6 o'clock is the ground. The 3 o'clock is the "key on" ignition 9 o'clock is to the sending unit.
If you pull the gauge it should read "E". Run a ground wire to the 6 o'clock terminal and a power wire to the 9 o'clock terminal.
The needle should go past the full mark. This confirms the gauge is good.

The sending unit is grounded with either a purple or black wire to the frame.
The factory sending unit power wire runs inside the frame and is an orange or tan color.
You can confirm ground with a test lead and verify the sending unit is good with a multimeter.
Resistance is 0 ohms empty and 90 ohms full.

Diagnosing gauges can be a headache; the wiring guide can help but overall it is pretty simple if you follow the basic steps.







 

Jgonick

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Usually PNK-30 runs from cluster to bulkhead. Then from bulkhead to sender unit on tank. If it is dual tanks its a little different. It runs to selector valve then it is pnk/wht & pnk/blk running to tanks

there is no 81 however 80 & 83 should be close if not identical.

wiring diagrams link

Good video explaining diagnosing
 

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tadslc

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Thanks guys,

Just haven't figured out these "foreign" wiring diagrams yet.

Also found a couple good YouTube videos on this.
 

tadslc

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Found these on another forum. Looks like you're looking for a Tan wire with a White stripe. The harness comes out of the bulkhead connector and runs down the drivers side frame rail with your tail light harness.

Do you know what year these are from?
Mine definitely has a pink wire coming from the sender, this shows Tan/White. Wouldn't think they'd change colors?
 

Jgonick

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I believe they used tan-30 in the 70s
 

consti2tion

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Do you know what year these are from?
Mine definitely has a pink wire coming from the sender, this shows Tan/White. Wouldn't think they'd change colors?
These were for a 1981. The color on my 1986 was a pink wire. But there are multiple pink wires on the on the cluster, pink with a black stripe I believe was 12v to the instrument cluster.
 
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