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| | | | Joined: Nov 2004 Posts: 1,552 Shop Shark | | Shop Shark Joined: Nov 2004 Posts: 1,552 | I am troubleshooting the fuel gauge in a '66 Chevy C10 and I have replaced the sending unit, fuel gauge and wire from sending unit to fuse block, to no avail. The under dash harness has been replaced, as well. The needle remains pegged to the past full position with the electrical connector plugged into the back of the back of the gauge, with power, without power or unplugged. Any pointers for correction of this situation?
Thanks.
Tony | | | | | Joined: Jul 2004 Posts: 5,708 'Bolter | | 'Bolter Joined: Jul 2004 Posts: 5,708 | Tony,
I might not understand the situation, but it sounds like the 'movement', or needle is mechanically stuck. Does the needle even give a hint of movement when disconnecting or reconnecting wires. Could it have been dropped or blasted in shipping. I'm afraid you will say the old gauge did this AND the new gauge acts the same.
Stuart | | | | | Joined: Jul 2004 Posts: 5,708 'Bolter | | 'Bolter Joined: Jul 2004 Posts: 5,708 | Tony,
A FULL gauge reading means a "open" between powered gauge and ground supplied by sender. You say you replaced the wire from gauge to fuse block but how about the wire from fuse block to sender. If this wire is 'open' the gauge will read full constantly.
The trick to prove the gauge is to turn the key on and using a small jumper, ground the wire in the fuse block to a clean good spot...the gauge should jump to EMPTY. That connection in the fuse block is not powered, it's just a connection for the wire back to the tank.
Stuart | | | | | Joined: Nov 2004 Posts: 1,552 Shop Shark | | Shop Shark Joined: Nov 2004 Posts: 1,552 | The fuel gauge, sending unit, wire from gauge to fuse block and wire from sending unit to fuse block have all been replaced. The needle still pegs, past full, to the right. I am stumped.
Tony | | | | | Joined: Jul 2004 Posts: 5,708 'Bolter | | 'Bolter Joined: Jul 2004 Posts: 5,708 | Tony, When you turn the key OFF, does the gauge change position. With 12 volts applied and no ground available, the gauge will read FULL. With 12 volts applied and a jumper from the sending unit terminal on the gauge to ground, the gauge should read MTY...if it doesn't do this, the gauge isn't functioning. If it does do that, then the wire back to the sending unit is open OR the sending unit/tank is not properly grounded. It's this simple. What happens when you bypass the connection at the fuse block and connect the two wire ends directly. Is there a connector on the back of the gauge that allows it to be connected one way only...keyed! http://rmcavoy.freeshell.org/diagrams/66cabwire.jpg Stuart | | | | | Joined: Nov 2004 Posts: 1,552 Shop Shark | | Shop Shark Joined: Nov 2004 Posts: 1,552 | Power or no power, the gauge is pegged past full. I will check another gauge to see if the replacement is faulty. I am stumped, but thanks for all the input.
Tony | | | | | Joined: Jun 2004 Posts: 8,597 Riding in the Passing Lane | | Riding in the Passing Lane Joined: Jun 2004 Posts: 8,597 | I answered your private message.
They say money can't buy happiness. It can buy old Chevy trucks though. Same thing. 1972 Chevy c10 Cheyenne SuperIn the Gallery Forum | | | | | Joined: Nov 2004 Posts: 1,552 Shop Shark | | Shop Shark Joined: Nov 2004 Posts: 1,552 | George:
Thanks for your prompt reply. I have read and responded to the PM.
Tony | | |
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