Analog Instrument Panels: Operation: Gauges: Fuel

Instrument Panel Cluster (IPC) operates fuel gauge by class 2 serial data messages from Powertrain Control Module (PCM). Fuel gauge indicates quantity of fuel in tank when ignition switch is in RUN position. When ignition switch is turned to OFF, LOCK, START or ACC position, pointer may come to rest at any position. PCM/VCM receives an input from fuel level sensor. Fuel level sensor is inside of fuel tank, and has a variable resistor that is controlled by the float. When fuel tank is full and ignition switch is in RUN position, PCM should receive a high resistance due to position of float. PCM interprets this signal and sends a class 2 serial data message to IPC indicating percentage of fuel in tank. Indicator on fuel gauge then moves to maximum position or FULL on gauge face. When fuel tank is empty, float in fuel tank is at the lowest position and resistance is low. PCM interprets this signal and sends a class 2 serial data message to IPC indicating percentage of fuel in tank. Indicator on fuel gauge then moves to minimum position or EMPTY on gauge face.