Fuel Gauge

The IPC displays the fuel level as determined by the PCM. The Body Control Module (BCM) receives a class 2 message from the PCM indicating the fuel level percent. The BCM converts the fuel level percent into a percent gage deflection. The IPC receives a message from the BCM via the Serial Peripheral Interface (SPI) indicating the requested gage position. The fuel gage defaults to E (empty) if:
^ The PCM detects a malfunction in the fuel level sensor circuit.
^ The BCM detects a loss of class 2 communications with the PCM.
^ The IPC detects a loss of SPI communications with the BCM.

When the fuel level is less than a pre-determined value, the low fuel indicator illuminates.