Instrument Panel, Gauges and Warning Indicators: Testing and Inspection
Gauge failures are often caused by defective wiring or grounds. The first step in locating trouble should be a thorough inspection of all wiring, terminals and printed circuits. If wiring is secured by clamps, check to see whether the insulation has been severed, thereby grounding the wire. In the case of a
fuel gauge installation, rust may cause failure by corrosion at the ground connection of the tank unit.