Falcon 2000 FQMC Fault Codes: Water Contamination & Fuel Probe Repair

March 2025

Example of a dirty fuel bay probe with contaminated terminal attachment areas.

Falcon FQMC Fault Codes Relating To Fuel Quantity Gauging Signal Outside Of Tolerance on your Falcon 2000 usually mean water has affected the probes in the fuel bay. These probes should be removed, inspected, and then cleaned. The water or condensation will not always be readily apparent during the inspection of the probe, which makes cleaning a very important step of the process.

Since this is a DC capacitance system, the wire connections on the probe are very sensitive to any resistance, and terminals should be carefully cleaned of tarnish. With the probe removed, the empty capacitance of the probe can be checked using a DC capacitance meter and following the probe capacitance chart in the Intertechnique probe’s maintenance manual.

Please reference FSA2000 28-40-12, which states the importance of purging the fuel bays of water on a regular schedule.

Example of a clean fuel bay probe.