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DTC P2450

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 P2450: Evaporative Emission (EVAP) System Leak Detection Pump Switching Valve Performance

Circuit/System Description

The evaporative emission (EVAP) system uses a EVAP leak detection pump to test for system leaks. The EVAP leak detection pump assembly consists of the following components:

    • EVAP leak detection pump with reference orifice
    • EVAP leak detection pump switching valve
    • EVAP leak detection pump pressure sensor

When the EVAP leak detection vacuum pump is ON, and the EVAP leak detection pump switching valve transitions from vent to not venting, pump, position, there should be an initial vacuum drop followed by a vacuum increase on a good system. The diagnostic looks for a difference relative to the reference vacuum, either an increase or decrease. No vacuum change indicates a problem with the EVAP leak detection pump switching valve and a P2450 is set. The switching valve is integral to the EVAP leak detection pump assembly and is non serviceable.

Conditions for Running the DTC
    • DTCs P043E, P043F, P0451, P1458, P145C, P145D, P0101, P0102, P0103, P0106, P0107, P0108, P0111, P0112, P0113, P0114, P0116, P0117, P0118, P0119, P0121, P0122, P0123, P0128, P012B, P012C, P012D, P0222, P0223, P0449, P0452, P0453, P0461, P0462, P0463, P0498, P0499, P0502, P0503, P06E4, P0722, P0723, P1221, P1459, P145A, P2066, P2067, P2068, P2400, P2401, P2402, P2418, P2419, P2420, P2537, P2610, U0073, U0074, U0140, U182D and P2422 are not set.
    • The purge solenoid valve is closed
    • The vent solenoid valve is closed
    • The vehicle is OFF
    • The refuelling request button pressed
    • A service bay test is not active
    • The EVAP leak detection pump switching valve transitions from vent to not venting, pump position
    • The EVAP leak detection vacuum pump is ON
    • The odometer greater than 16 km (10 mi)
    • The barometric pressure (BARO) is between 70-110 kPa (10-16 PSI)
    • The fuel level is between 10-90%
    • The engine coolant temperature is less than 40°C (104°F)
    • The inlet air temperature is between 4-45°C (39-113°F)
    • The system voltage is greater than 10 V
    • The vehicle speed less than 1.6 km/h (1 MPH)
    • There are three possible time windows for this test to run. Up to that point, and through this time period, the propulsion system must not be active. These time windows are: 5.0, 7.0 or 9.5 hours.

Conditions for Setting the DTC

The EVAP leak detection pump is commanded ON, and the EVAP leak detection pump switching valve transitions from vent to not venting, pump, position. If all conditions are not met after 5 s, then the EVAP leak detection pump switching value is stuck and the P2450 sets.

Action Taken When the DTC Sets

DTC P2450 is a Type B DTC.

Conditions for Clearing the DTC

DTC P2450 is a Type B DTC.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Evaporative Emission Control System Description

Hybrid Modes of Operation 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. Vehicle in Service Mode, observe the EVAP leak detection pump switching valve command parameter with a scan tool.
    2. ⇒The parameter should display Venting or Not Venting
  2. 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.

Component Testing

Note: Ensure that the vehicle underbody temperature is similar to the ambient temperature and allow the surrounding air to stabilise before starting the diagnostic procedure.

  1. Vehicle in Service Mode, command the EVAP Test with the scan tool and observe the following parameters.
    2. • The switching valve command status should change from Venting to Not Venting.
    • The EVAP leak detection pump command should show On
    • The EVAP vent solenoid valve command should show On
  2. Observe and note the EVAP leak detection pump pressure and Fuel Tank Pressure.
    3. ⇒Both pressures should drop.
  3. If status changes, but no pressure drop, remove the vent pipe and the fresh air pipe from the EVAP leak detection pump assembly.
    4. ⇒Look into the pump openings, inspect and repair any of the conditions listed below:
    • The EVAP leak detection pump to the vent solenoid tube and clamps for damage or restriction
    • Missing or damaged EVAP leak detection pump O-rings
    • The fresh air tube near the fuel fill pocket for a restriction
    • The fresh air tube for a restriction
  4. If all components test normal, replace the Q63 EVAP leak detection pump assembly.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure

    •  Evaporative Emission System Vacuum Leak Detection Pump Replacement
    • Control Module References for ECM replacement, setup, and programming
   


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