Jeep CJ Gauge & Sender Diagnostics - 4x4Wire Jeep CJ Gauge & Sender Diagnostics. Short Cuts: By: John Foutz - 3/2000 DO NOT hold it for very long in this position, just touch and release the wire. If the gauge does not move from EMPTY either the wiring has an open circuit (no voltage, or no connection to ground) or he gauge is bad. If it does move, the sending unit is bad. Jeep Knowledge Center - CJ Gauge Troubleshooting Both Jeep parts gauges have wiring terminals and a large jumper/regulator strap running between them. The fuel gauge terminals are labeled: S, A and I. Fuel gauge S terminal has a pink wire and runs to the fuel sender. Fuel gauge A terminal is the 12V side of the jumper/regulator strap.