DTC P2066 5.7L
DTC Descriptor
DTC P2066: Fuel Level Sensor 2 PerformanceDiagnostic Fault Information
Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
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 (left) fuel level sender and the secondary (right) fuel level sender changes resistance based on fuel level. The powertrain control module (PCM) monitors the signal circuits of the primary (left) fuel level sender and the secondary (right) 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 PCM senses a high signal voltage on both the signal circuits of the primary (left) fuel level sender and the secondary (right) fuel level sender. When the fuel tanks are empty, the resistances of the fuel level senders are low and the PCM senses a low signal voltage. The PCM uses the signal circuits of the primary (left) fuel level sender and the secondary (right) fuel level sender in order to calculate the percentage of remaining fuel in the tank. The PCM 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
The ignition is ON, with the engine running.
Conditions for Setting the DTC
The PCM does not detect a change in the secondary tank fuel level of at least 3 L (0.79 gal) over a distance of 320 km (200 miles)
Action Taken When the DTC Sets
| • | The fuel gage defaults to empty. |
| • | The driver information center (DIC) displays the FUEL LEVEL LOW message. |
| • | The PCM records the operating conditions at the time that the diagnostic test 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 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
| • | Engine Controls Schematics for the 5.7L engine |
Connector End View Reference
| • | Powertrain Control Module Connector End Views for the 5.7L engine |
Description and Operation
Fuel Gage Description and Operation
Electrical Information Reference
Scan Tool Reference
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 no interference is present, perform the fuel level sensor component test before replacing the secondary (right) fuel level sensor.
| ⇒ | If any interference is present, remove the obstruction. |
Component Testing
- Ignition OFF, disconnect the harness connector at the secondary (right) fuel level sensor.
- While sweeping the secondary (right) 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 (right) fuel level sensor. |
Repair Instructions
| • | Secondary Fuel Tank Module Replacement for the 5.76L engine |
| • | Control Module References for the PCM replacement, setup, and programming |
DTC P2066 2.8L and 3.6L
DTC Descriptor
DTC P2066: Fuel Level Sensor 2 PerformanceDiagnostic Fault Information
Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
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 (left) fuel level sender and the secondary (right) fuel level sender changes resistance based on fuel level. The engine control module (ECM) monitors the signal circuits of the primary (left) fuel level sender and the secondary (right) 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 (left) fuel level sender and the secondary (right) 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 (left) fuel level sender and the secondary (right) 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
| • | The engine is running. |
| • | No fuel level sensor signal failure present. |
| • | 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 (.264 gal) over a range of 30 L (7.92 gal) or 45.6 percent of the secondary fuel tank. |
| • | The above condition is present for greater than 300 seconds. |
Action Taken When the DTC Sets
| • | The fuel gage defaults to empty. |
| • | The driver information center (DIC) displays the FUEL LEVEL LOW message. |
| • | 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
| • | Engine Controls Schematics for the 3.6L engine |
| • | Engine Controls Schematics for the 2.8L engine |
Connector End View Reference
| • | Engine Control Module Connector End Views for the 3.6L engine |
| • | Engine Control Module Connector End Views for the 2.8L engine |
Description and Operation
Fuel Gage Description and Operation
Electrical Information Reference
Scan Tool Reference
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 no interference is present, perform the fuel level sensor component test before replacing the secondary (right) fuel level sensor.
| ⇒ | If any interference is present, remove the obstruction. |
Component Testing
- Ignition OFF, disconnect the harness connector at the secondary (right) fuel level sensor.
- While sweeping the secondary (right) 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 (right) fuel level sensor. |
Repair Instructions
| • | Secondary Fuel Tank Module Replacement for the 3.6L engine |
| • | Secondary Fuel Tank Module Replacement for the 2.8L engine |
| • | Control Module References for the ECM replacement, setup, and programming |
