vannmike

I have a a 77, which I believe is the model year that went to the printed circuit board on back of the gauge cluster, with the plug. I heard that even though most of the gauges are wired through this one plug, the fuel gauge is not. I'm trying to determine which wires go to the sending unit. It looks like the wires coming off the sending unit are 1 black and 1 tan wire, and I see a black wire and tan wire in the plug, but that would contradict what I heard about the sending unit wiring being separate from the plug, thoughts?

wendellp601

Fuel gauge wiring is in the harmonica connector.
The tan wire is still the Ohms signal from the sending unit.
You really need a wiring diagram. Don't rely on what you heard.
There is a user on this forum called Papawana.
He'll send you a wiring diagram if you send him a PM.

0Willcox Corvette

The info below should help you resolve any issue you have with a fuel gauge.

The first question is what is the dash unit doing... it will tell you in most cases where the problem is.

Secondly... Pull the ohms wire from the sending unit and with the key on see what the dash unit reads... it should go to full. Next ground out the ohms wire and the gauge should go to empty... <--- Show in the video below.

If the gauge pass's the two test above the issue is in the sender or the sender ground. By doing that test you also validate the wire from the sender to the dash unit. If you read my tech page posted below it goes into great detail about how to find most issues.

1977-1982 Corvette Fuel Gauge and Sending Unit Testing

Willcox Corvette Fuel Gauge Video - What can your non working gauge tell you!




-Willcox

vannmike

Thanks Wilcox. I'm looking to install an autometer gauge and was trying to use the existing wiring.

0Willcox Corvette

Well the wiring is through the pcb.. I have a schematic of all the wires going to the pcb if you need it.

This should help you sort out the wires at the connection at the connector. You may have to just mount the gauges in the metal housing and then cut off the pcb connector and hardware... If so the picture below should help you get there.



-Willcox

vannmike

Thanks Wilcox. I would love to have a copy of the schematic for the wiring in the pcb

0Willcox Corvette

The connector with the wire colors can be found on page 4 of the Help page I posted above. All you have to do is match up the connector with the backside of the last image I posted.

Willcox