Circuit Description
The fuel level sensor changes resistance based on fuel level. Powertrain Control Module (PCM) monitors signal circuit (Purple wire) of fuel level sensor in order to determine fuel level. When fuel tank is full, sensor resistance is high and PCM senses a high signal voltage. When fuel tank is empty, sensor resistance is low and PCM senses a low signal voltage. PCM uses signal circuit of fuel level sensor in order to calculate total remaining fuel (percent) in fuel tank. See Fig 1 . PCM sends fuel level percent via class 2 serial data circuit (Dark Green wire to splice pack SP205; Gray wire from SP205) to Instrument Panel Cluster (IPC) in order to control fuel gage. Fuel level information is also used for misfire and EVAP diagnostics.
DTC P0462 will set when IPC senses fuel level signal voltage is less than 3.5 percent (0.4 volt) for more than 10 seconds. When DTC P0462 sets, fuel gauge defaults to empty, check gauges indicator illuminates, PCM records operating conditions at time diagnostic fails and PCM displays failure information in FAILURE RECORDS on scan tool.
A current DTC P0462 becomes a history DTC if condition for setting DTC is no longer present. A history DTC P0462 will clear after 40 consecutive ignition cycles if condition for setting DTC is no longer present. DTC will also clear when scan tool is used to clear DTCs.