2010 Cadillac Truck SRX AWD V6-3.0L Page 1500
for purge valve.
4. Command the evaporative emission canister purge solenoid valve to 50 percent with a scan tool, or the evaporative emission canister vent
solenoid valve ON and OFF. The test lamp should respond to the command.
瀚慖f the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the K20 ECM.
瀚慖f the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace
the K20 ECM.
5. If all circuits test normal, replace the appropriate solenoid valve.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
* Evaporative Emission Canister Purge Solenoid Valve Replacement (LF1) (See: Powertrain Management/Emission Control
Systems/Evaporative Emissions System/Canister Purge Solenoid/Service and Repair)Evaporative Emission Canister Purge Solenoid Valve
Replacement (LAU) (See: Powertrain Management/Emission Control Systems/Evaporative Emissions System/Canister Purge
Solenoid/Service and Repair)
* Evaporative Emission Canister Vent Solenoid Valve Replacement (NT7, NU5) (See: Powertrain Management/Emission Control
Systems/Evaporative Emissions System/Evaporative Emission Control Canister/Canister Vent Valve/Service and Repair)
* Control Module References (See: Testing and Inspection/Programming and Relearning) for ECM replacement, setup, and programming
P0451
DTC P0451-P0454 (LF1)
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System
Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an
overview of the diagnostic approach.
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC P0451
- Fuel Tank Pressure Sensor Performance
DTC P0452
- Fuel Tank Pressure Sensor Circuit Low Voltage
DTC P0453
- Fuel Tank Pressure Sensor Circuit High Voltage
DTC P0454
- Fuel Tank Pressure Sensor Intermittent
Diagnostic Fault Information
Typical Scan Tool Data
