Fault Phenomenon: Caterpillar 785 mining truck instrument displays “Water in Fuel” warning light, engine power limited.

Troubleshooting Process:
– Checked fuel-water separator: excessive water accumulation at bottom.
– Checked sensor: float stuck or electrodes corroded.
– Checked fuel: sampling reveals excessive water content.
– Checked wiring: sensor wiring shorted.

Root Cause: Water accumulated at the bottom of the fuel tank or poor fuel quality allowed moisture to enter, causing the fuel-water separator water level to reach the limit and trigger the sensor.

Required Parts: Drain water from fuel-water separator, replace fuel filter, replace sensor if damaged.