Fuel Gauge Inoperative or Inaccurate

CIRCUIT DESCRIPTION

The IPC monitors the fuel level sent by the Body Control Module (PZM) via Class 2 serial data bus. The IPC software controls either a digital gauge consisting of a two-digit numeric seven-segment display or an analog gauge consisting of a needle pointer. The IPC interpolates and scales the fuel level information received from the PZM.

NORMAL DIGITAL OPERATION:

Fuel level is displayed as the filtered fuel level in whole gallons (liter). When the IPC reads above 18.5 gallons the display will read "F". Readings between 18.5 and 2.5 gallons will be displayed as whole gallon numbers. When the level reaches 2.5 gallons the display will read "E". When the level reaches 1.5 gallons the "E" will flash and a "Fuel Level Very Low" message will appear on the DIC.

NORMAL ANALOG OPERATION

Fuel level is displayed as the filtered fuel level as a digital display. When the level reaches 1.2 gallons a "Fuel Level Very Low" message will appear on the DIC, unless suppressed by the option byte setting.

DISPLAY OFF WARNING

If the vehicle is operating in "Display OFF" mode and the fuel level falls below 4 gallons, all displays will return to active mode and the DIC will display "CHECK FUEL GAGE" unless suppressed by the option byte setting.