P2068

DTC P2068

CIRCUIT DESCRIPTION
The primary fuel level sender and the secondary fuel level sender changes resistance based on fuel level. The powertrain control module (PCM) monitors the signal circuits of the primary fuel level sender and the secondary fuel level sender in order to determine the fuel level. When the fuel tanks are full, the resistance of both fuel level senders are low and the PCM senses a low signal voltage on both the signal circuits of the primary fuel level sender and the secondary fuel level sender. When the fuel tanks are empty, the resistance of the fuel level senders are high and the PCM senses a high signal voltage. The PCM uses the signal circuits of the primary fuel level sender and the secondary fuel level sender in order to calculate the percentage of the remaining fuel in the tank. The PCM sends the fuel level percent via the class 2 serial data circuit to the instrument cluster in order to control the fuel gage. The fuel level information is also used for misfire and evaporative emission (EVAP) diagnostics.

This diagnostic tests for a higher than normal secondary fuel level sender signal.

DTC DESCRIPTOR
This diagnostic procedure supports the following DTC:
DTC P2068 Fuel Level Sensor 2 Circuit High Voltage

CONDITIONS FOR RUNNING THE DTC
The engine is running.

CONDITIONS FOR SETTING THE DTC
- The secondary sender output is greater than 2.9 volts.
- The above condition is present for greater than 30 seconds.

ACTION TAKEN WHEN THE DTC SETS
- The fuel gage defaults to empty.
- The low fuel indicator illuminates.
- The PCM records the operating conditions at the time the diagnostic fails. The PCM displays the failure information in the Failure Records on the scan tool.

CONDITIONS FOR CLEARING THE DTC
- The DTC becomes history when the conditions for setting the DTC are no longer present.
- The history DTC clears after 40 malfunction free warm-up cycles.
- The PCM receives the clear code command from the scan tool.

DIAGNOSTIC AIDS
Use the Freeze Frame and/or Failure Records data in order to locate an intermittent condition. If you cannot duplicate the DTC, the information included in the Freeze Frame and/or Failure Records data may aid in determining the number of miles since the DTC set. The Fail Counter and Pass Counter can also aid in determining the number of ignition cycles that the diagnostic reported a pass and/or fail. Operate the vehicle within the same freeze frame conditions, including those for RPM, for engine load, for vehicle speed, for temperature, and for others. This will isolate when the DTC failed.

TEST DESCRIPTION

Steps 1-10:

Steps 11-12:

The number below refers to the step number on the diagnostic table.
3. Tests for the proper operation of the circuit in the low voltage range.