Diagnostic Instructions
DTC Descriptor
DTC P2066: Fuel Level Sensor 2 Performance
Diagnostic Fault Information
Circuit
| Short to Ground
| Open/High Resistance
| Short to Voltage
| Signal Performance
|
Fuel Level Sensor Reference Voltage Circuit
| P2067
| --
| --
| P2066
|
Fuel Level Sensor Signal Secondary Circuit
| P2067
| P2068
| P2068
| P2066
|
Fuel Level Sensor Low Reference Circuit
| --
| P2068
| P2068
| P2066
|
Circuit/System Description
The primary fuel level sender and the secondary fuel level sender changes resistance based on fuel level. The engine control module (ECM) 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 tank is full, the resistances of both fuel level senders are high and the ECM senses a high 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 resistances of the fuel level senders are low and the ECM senses a low signal voltage. The ECM uses the signal circuits of the primary fuel level sender and the secondary fuel level sender in order to calculate the percentage of remaining fuel in
the tank. The ECM sends the fuel level percentage via serial data circuit to the instrument cluster in order to control the fuel gage.
Conditions for Running the DTC
| • | No fuel level sensor signal failure present. |
| • | The fuel level state is stable. |
Conditions for Setting the DTC
| • | The ECM detects a difference between the engine consumed fuel and change of the fuel level signal of less than 1 L (0.26 gallons) over a range of 30 L (7.92 gallons) or 45.6 percent of the secondary fuel tank. |
| • | The above condition is present for about 300 seconds. |
Action Taken When the DTC Sets
| • | The fuel gage defaults to empty. |
| • | The low fuel indicator illuminates. |
| • | The ECM records the operating conditions at the time that the diagnostic test fails. The ECM 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 ECM receives a clear code command from the scan tool. |
Diagnostic Aids
A partially filled fuel tank and filling the fuel tank with the ignition ON or engine RUNNING may cause an inaccurate or erratic fuel gage. This condition may cause a fuel system DTC to set and the fuel gage to default to empty. Refer to
Fuel Gage Description and Operation
Reference Information
Schematic Reference
Connector End View Reference
Description and Operation
Fuel Gage Description and Operation
Electrical Information Reference
Scan Tool Reference
Scan Tool Data List
Circuit/System Testing
- Ignition OFF, remove the secondary fuel level sender and verify that there are no obstructions interfering with the fuel level sender.
| ⇒ | If any interference is present, remove the obstruction. |
- If no interference is present, perform the fuel level sensor component test before replacing the secondary fuel level sensor.
Component Testing
- Ignition OFF, disconnect the harness connector at the secondary fuel level sensor.
- While sweeping the secondary fuel level sensor through its full range of motion, test for a minimum value less than 41 ohms and a maximum value greater than 119 ohms of resistance between signal terminal A and the low reference terminal
D.
| ⇒ | If not within the specified range, replace the secondary fuel level sensor. |
Repair Instructions
Perform the
Diagnostic Repair Verification
after completing the diagnostic procedure.
