Circuit/System Description

The fuel level sensor changes resistance based on fuel level and is wired to the K111 Fuel Pump Driver Control Module. The K111 Fuel Pump Driver Control Module sends the fuel level sensor reading to the K20 Engine Control Module/K45 Powertrain Control Module via serial data. The K20 Engine Control Module/K45 Powertrain Control Module monitors the fuel level sensor signal in order to determine the fuel level. When the fuel tank is full, the resistances of both fuel level sensors are low. When the fuel tank is empty, the resistances of the fuel level sensors are high. The K20 Engine Control Module/K45 Powertrain Control Module uses the signal voltages of the primary fuel level sensor and the secondary fuel level sensor (integrated in the fuel tank) to calculate the percentage of remaining fuel in the tank. The K20 Engine Control Module/K45 Powertrain Control Modulesends the fuel level percentage via serial data to the K9 Body Control Module (BCM). The BCM then sends the fuel level percentage via serial data to the A11 Radio to control the indicated fuel level on the driver information display