PRE-RELEASE
DTC P0452 or P0453 (LAU)
| DTC P0452 or P0453 (LAU) |
| Diagnostic Instructions |
| • |
Perform the
Diagnostic System Check - Vehicle
prior to using this diagnostic procedure.
|
|
| • |
Review
Strategy Based Diagnosis
for an overview of the diagnostic approach.
|
|
| • |
Diagnostic Procedure Instructions
provides an overview of each diagnostic category.
|
|
| DTC Descriptors |
DTC P0452
Fuel Tank Pressure Sensor Circuit Low Voltage
DTC P0453
Fuel Tank Pressure Sensor Circuit High Voltage
| Diagnostic Fault Information |
| Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
| 5-Volt Reference | P0452, P0642 | P0452, P0641 | P0453, P0643 | P0641, P0642, P0643 |
| Fuel Tank Pressure Sensor Signal | P0452 | P0452 | P0453 | - |
| Low Reference | - | P0446 | - | - |
| Typical Scan Tool Data |
Fuel Tank Pressure Sensor
| Circuit | Short to Ground | Open | Short to Voltage |
| Operating Conditions: Engine operating in Closed Loop at idle Parameter Normal Range: 0.2-4.8 V | |||
| 5-Volt Reference | 0 V | 0 V | 5 V |
| Fuel Tank Pressure Sensor Signal | 0 V | 0 V | 5 V |
| Low Reference | - | 4.2 V | - |
| Circuit/System Description |
The evaporative emission (EVAP) system is used to store fuel vapors in order to reduce the amount of fuel vapors into the atmosphere. The fuel tank pressure sensor is only used for EVAP system diagnostics. The fuel tank pressure sensor is a transducer that varies resistance according to changes in the fuel tank pressure. The engine control module (ECM) monitors the fuel tank pressure sensor signal in order to detect vacuum decay and excess vacuum during the EVAP system diagnostic test. The ECM supplies a 5-volt reference and a low reference circuit to the fuel tank pressure sensor.
| Fuel Tank Pressure Sensor Signal Voltage | Fuel Tank Pressure |
| High, Approximately 1.5 Volts or More | Negative Pressure/Vacuum |
| Low, Approximately 1.5 Volts or Less | Positive Pressure |
| Conditions for Running the DTC |
| • |
The engine is operating.
|
|
| • |
The DTCs run continuously once the above conditions are met for 14 seconds, 10 seconds for LLT.
|
|
| Conditions for Setting the DTC |
P0452
The ECM detects the fuel tank pressure sensor signal voltage is less than 0.12 volt for 4 seconds, or a cumulative of 30 seconds.P0453
The ECM detects the fuel tank pressure sensor signal voltage is greater than 4.85 volts for 4 seconds, or a cumulative of 30 seconds.| Action Taken When the DTC Sets |
DTC P0452 and P0453 are Type B DTCs.
| Conditions for Clearing the MIL/DTC |
DTC P0452 and P0453 are Type B DTCs.
| Diagnostic Aids |
If a shared 5-volt reference circuit is shorted to ground or shorted to a voltage, other 5-volt reference circuits may be affected.
| Reference Information |
Schematic Reference
Engine Controls Schematics (3.0L (LF1)) Engine Controls Schematics (2.8L (LAU))
Connector End View Reference
Component Connector End Views
Description and Operation
Evaporative Emission Control System Description
Electrical Information Reference
| • |
Circuit Testing
|
|
| • |
Connector Repairs
|
|
| • |
Testing for Intermittent Conditions and Poor Connections
|
|
| • |
Wiring Repairs
|
|
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References for scan tool information
| Circuit/System Verification |
| 1. |
Ignition ON, check the diagnostic trouble code (DTC) information with a scan tool. DTCs P0641, P0642 or P0643 should not set.
|
|
| 2. |
If a DTC is set, refer to
DTC P0641-P0643, P0651-P0653, or P0697-P0699 (ECM, LAU)
.
|
|
| 3. |
Observe the Fuel Tank Pressure Sensor voltage parameter. The Fuel Tank Pressure sensor voltage should be between 0.13-4 volts.
|
|
| 4. |
Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the freeze frame/failure records data.
|
|
| Circuit/System Testing |
| 1. |
Ignition OFF, disconnect the harness connector at the B150 fuel tank pressure sensor.
|
|
| 2. |
Ignition OFF, test for less than 5 Ω of resistance between the low reference circuit terminal 1 and ground.
|
|
| 3. |
If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K20 ECM.
|
|
| 4. |
Ignition ON, test for 4.8-5.2V between the 5V reference circuit terminal 3 and ground.
|
|
| 5. |
If less than the specified range, test the 5V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K20 ECM.
|
|
| 6. |
If greater than the specified range, test the 5V reference circuit for a short to voltage. If the circuit tests normal, replace the ECM.
|
|
| 7. |
Verify the scan tool B150 fuel tank pressure sensor parameter is less than 0.2V.
|
|
| 8. |
If greater than the specified range, test the signal circuit's pin 2 for a short to voltage. If the circuit tests normal, replace the K20 ECM.
|
|
| 9. |
Install a 3A fused jumper wire between the signal circuit terminal 2 and the 5V reference circuit terminal 3. Verify the scan tool fuel tank pressure sensor parameter is greater than 4.7V.
|
|
| 10. |
If less than the specified range, test the signal circuit for short to ground or an open/high resistance. If the circuit tests normal, replace the K20 ECM.
|
|
| 11. |
If all circuits test normal, test or replace the B150 fuel tank pressure sensor.
|
|
| Repair Instructions |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • |
Fuel Tank Pressure Sensor Replacement
|
|
| • |
Control Module References
for ECM replacement, setup, and programming
|
|
