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DTC P043E, P043F, or P145F

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 P043E: Evaporative Emission (EVAP) System Reference Orifice Flow Insufficient

DTC P043F: Evaporative Emission (EVAP) System Reference Orifice Flow Excessive

DTC P145F: Evaporative Emission (EVAP) System Reference Orifice 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

The engine control module (ECM) monitors the pressure across the reference orifice with the EVAP leak detection pump pressure sensor. When all conditions are met, the ECM commands the vacuum pump ON and monitors the EVAP leak detection pump pressure sensor. If the ECM detects the pressure is too low, too high, or not stabilised, a DTC sets.

Conditions for Running the DTC
    • DTCs P0101, P0102, P0103, P0106, P0107, P0108, P0111, P0112, P0113, P0114, P0116, P0117, P0118, P0119, P0121, P0122, P0123, P0128, P012B, P012C, P012D, P0222, P0223, P0449, P0451, P0452, P0453, P0461, P0462, P0463, P0498, P0499, P0502, P0503, P06E4, P0722, P0723, P1221, P1458, P1459, P145A, P145C, P145D, P145E, P2066, P2067, P2068, P2400, P2401, P2402, P2418, P2419, P2420, P2421, P2422, P2450, P2537, P2610, U0073, U0074, U0140, or U182D is not set.
    • The vehicle is OFF.
    • The propulsion system is not active.
    • The refueling request button is not pressed
    • A service bay test is not active
    • The purge valve is closed
    • The vent solenoid valve is closed
    • The EVAP Leak Detection Pump switching valve is in the vent position
    • The EVAP Leak Detection Pump vacuum pump is ON
    • The odometer is 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

P043E

    • The ECM detects the EVAP leak detection pump pressure is greater than 4 kPa (0.58 PSI) after 6 minutes.
        OR
    • The ECM detects the EVAP leak detection pump pressure is greater than 4.5 kPa (0.65 PSI) after 10 s.

P043F

    • The ECM detects the EVAP leak detection pump pressure is less than 1.18 kPa (0.17 PSI) after 6 minutes.
        OR
    • The ECM detects the EVAP leak detection pump pressure is less than 1.18 kPa (0.17 PSI) after 30 s.

P145F

The ECM detects the difference between the first EVAP leak detection pump pressure measurement is greater than 0.51 kPa (0.073 PSI) then the second measurement after 30 s.

Action Taken When the DTC Sets

DTCs P043E, P043F and P145F are Type B DTCs.

Conditions for Clearing the DTC

DTCs P043E, P043F and P145F are Type B DTCs.

Diagnostic Aids
    • Inspect the tube and clamps from the EVAP leak detection pump to the vent solenoid for damage. A damage/open tube may allow debris to enter the pump and plug the reference orifice.
    • Remove the EVAP leak detection pump and look inside the pump opening for any debris that could restrict or plug the reference orifice. The reference orifice is a small opening at the 2 o'clock position in the pump vacuum opening. Inspect for missing or damage O-rings.
    • With the fresh air tube removed from the EVAP leak detection pump assembly, blow controlled air, 5-10 PSI, into this tube. There should be air escaping from behind the fuel fill pocket indicating this tube and filter are not restricted.
    • A switching valve stuck in the pump position can cause insufficient flow.
    • This part is not serviceable. It is very important that no debris be found in the pump fresh air inlet or vacuum openings, the tube between the vent solenoid valve and EVAP leak detection pump assembly as this could cause a P043E to set.

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, verify the scan tool BARO pressure is within the range specified in the Altitude Versus Barometric Pressure table.
  2. Record the EVAP leak detection pump pressure sensor reading. The reading should be 1.18-4 kPa (0.17-0.58 PSI) less than BARO.
  3. Command the EVAP Leak Detection Pump Command ON with the scan tool and monitor the EVAP leak detection pump pressure. Observe this for a steady or increasing PSI.
    4. • If the PSI is increasing, then there is a restriction in the orifice.
    • If the PSI is steady, then the orifice is good.
  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

Note: The reference orifice is a small opening at the 2 o'clock position in the pump vacuum opening.

  1. Vehicle OFF, remove the Q63 EVAP leak detection pump. Inspect the reference orifice within the pump for a restriction/blockage. The reference orifice should not be restricted.
    2. ⇒If the reference orifice is restricted, inspect and repair any of the conditions listed below:
    • The EVAP leak detection pump to the vent solenoid tube and clamps for damage
    • A missing or damage 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
  2. If all components test normal, replace the Q63 EVAP system 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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