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**VetteVet** · 10-25-2018, 01:53 PM

Since you hard wired your cluster you don't have the circuit board but the stock truck cluster has the power feed for the fuel gauge and the temp gauge wired together like this:

Name: guage wiring.jpg
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Name: guage wiring.jpg
Views: 662
Size: 42.1 KB

This is power from the no, 3 terminal which is key on power for the fuel and temperature gauges and the sender wire for the fuel gauge is the no. 4 terminal on the fuel gauge and the no. 6 wire for the temperature gauge. these sender wires must be stand alone wires with nothing added. Looking at the panel from the back the power wire is on the right and the sender wire is on the left.

I don't know how the !992 blazer fuse panels are wired but if you look at the gauge cluster, it looks like the 67 to 72 trucks gauge cluster
I hope you can sort it out with my diagram and explanation.

The sender wire should be the one on the left (brown/yellow stripe. I assume the two tan wires on the right terminal are power wires for the fuel and temperature gauges. If so they would be correct.
I read that you grounded the two gauges to the third terminal post on the gauges but I also read that you grounded the sender wires which you can't do or the fuel gauge will read empty and the temp gauge will read full hot. If you do not connect the sender wire on the fuel gauge to anything but the sending unit in the tank, the gauge will read way past full like your picture shows. The sender wire for the fuel gauge goes to the stock fuse panel on a terminal there and then on to the fuel sending unit in the tank.

If that wire is grounded some where the gauge will read empty, if it is not connected to anything but the sending unit or if the sending unit and tank are not grounded the gauge will read way over full. This may be your problem. Take the wire off the sending unit (key on) and take the reading, should show way past full, now ground the sending wire, it should read empty, Put it back on the sending unit terminal, If it reads way past full, run a wire to the sending unit flange and see if it reads correctly.

What ever you do, don't put 12 volts on the sender wire to the tank sender.

10-25-2018, 01:53 PM	#3
VetteVet Msgt USAF Ret Join Date: Jan 2005 Location: Kalamazoo, Michigan Posts: 8,703	Re: Fuel Gauge Woes Since you hard wired your cluster you don't have the circuit board but the stock truck cluster has the power feed for the fuel gauge and the temp gauge wired together like this: This is power from the no, 3 terminal which is key on power for the fuel and temperature gauges and the sender wire for the fuel gauge is the no. 4 terminal on the fuel gauge and the no. 6 wire for the temperature gauge. these sender wires must be stand alone wires with nothing added. Looking at the panel from the back the power wire is on the right and the sender wire is on the left. I don't know how the !992 blazer fuse panels are wired but if you look at the gauge cluster, it looks like the 67 to 72 trucks gauge cluster I hope you can sort it out with my diagram and explanation. The sender wire should be the one on the left (brown/yellow stripe. I assume the two tan wires on the right terminal are power wires for the fuel and temperature gauges. If so they would be correct. I read that you grounded the two gauges to the third terminal post on the gauges but I also read that you grounded the sender wires which you can't do or the fuel gauge will read empty and the temp gauge will read full hot. If you do not connect the sender wire on the fuel gauge to anything but the sending unit in the tank, the gauge will read way past full like your picture shows. The sender wire for the fuel gauge goes to the stock fuse panel on a terminal there and then on to the fuel sending unit in the tank. If that wire is grounded some where the gauge will read empty, if it is not connected to anything but the sending unit or if the sending unit and tank are not grounded the gauge will read way over full. This may be your problem. Take the wire off the sending unit (key on) and take the reading, should show way past full, now ground the sending wire, it should read empty, Put it back on the sending unit terminal, If it reads way past full, run a wire to the sending unit flange and see if it reads correctly. What ever you do, don't put 12 volts on the sender wire to the tank sender. __________________ VetteVet metallic green 67 stepside 74 corvette convertible 1965 Harley sportster 1995 Harley wide glide Growing old is hell, but it beats the alternative. Last edited by VetteVet; 10-25-2018 at 02:27 PM.