Diagnostic Instructions

DTC Descriptors

DTC P2419: Fuel Tank Pressure (FTP) Control Solenoid Control Circuit Low Voltage

DTC P2420: Fuel Tank Pressure (FTP) Control Solenoid Control Circuit High Voltage

Diagnostic Fault Information

EVAP Canister Vent Solenoid Valve

Circuit	Short to Ground	Open/High Resistance	Short to Voltage	Signal Performance
Ignition 1 Voltage	P0441, P2420	P0441, P2420	--	--
EVAP Vent Valve Control Circuit	P043E, P043F, P2401, P2402, P2419	P0441, P2420	P0441, P2420	--

EVAP System Flow Conditions

Component	Cause	DTCs
EVAP Vent Solenoid Valve	Stuck Open, Leaking	P0441, P0455, P2420
	Stuck Closed, Blocked or Restricted Passages	P0441, P0455

Circuit/System Description

The diagnostic strategy for the evaporative emission (EVAP) system uses a vacuum pump to test for system leaks, after the engine is OFF. A unique fuel tank, EVAP canister, and EVAP vacuum leak pump work together to provide enhanced system diagnosis. The vacuum leak pump, the fuel tank pressure (FTP) sensor and the EVAP canister vent valve are all integral parts of one assembly. The assembly is attached directly to the EVAP canister, located near the fuel tank.

After the vehicle has sat with the engine OFF for greater than 5 hours and the engine coolant temperature is less than 35°C (95°F), a comprehensive diagnostic is enabled. The complete diagnostic test can take up to 15 minutes to run, with leak detection comprising the largest portion of the test.

The EVAP canister vent solenoid valve controls the entry of air used to purge fuel vapors from the EVAP canister. Ignition voltage is supplied directly to the EVAP vent solenoid valve. The powertrain control module (PCM) controls the solenoid by grounding the control circuit with a solid state device called a driver. The PCM can determine if the EVAP purge solenoid is operating correctly by monitoring the changes in fuel tank pressure.

The following table illustrates the relationship between the ON and OFF states, and the OPEN or CLOSED states of the EVAP canister purge and vent valves.

Control Module Command	EVAP Canister Purge Valve	EVAP Canister Vent Valve
ON	Open	Closed
OFF	Closed	Open

Conditions for Running the DTC

Conditions for Setting the DTC

P2419

The powertrain control module (PCM) has determined the EVAP vent solenoid may be stuck ON, CLOSED, because vacuum pressure is too high.

P2420

The powertrain control module (PCM) has determined the EVAP vent solenoid may be stuck OFF, OPEN, because vacuum pressure was not obtained.

Action Taken When the DTC Sets

DTC P2419 and P2420 are Type B DTCs.

Conditions for Clearing the DTC

DTC P2419 and P2420 are Type B DTCs.

Reference Information

Schematic Reference

Engine Controls Schematics

Description and Operation

Evaporative Emission Control System Description

Connector End View Reference

Component Connector End Views

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools

J 23738-A Vacuum Pump

Circuit/System Verification

1. Command the EVAP vent solenoid ON and OFF with a scan tool. You should hear the solenoid click when commanded ON and OFF.
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.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the EVAP canister.
2. Ignition ON, verify a test lamp illuminates between the ignition 1 voltage circuit terminal 9 and ground.

⇒	If the test lamp does not illuminate, test the ignition 1 voltage circuit for a short to ground or an open/high resistance. If the circuit tests normal and the ignition 1 voltage circuit fuse is open, test all components connected to the ignition 1 voltage circuit and replace as necessary.

3. Ignition OFF, connect a test lamp between the control circuit terminal 8 and the ignition 1 voltage circuit terminal 9.
4. Ignition ON, command the EVAP vent solenoid ON and OFF with a scan tool. The test lamp should illuminate ON and OFF with each command.

⇒	If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the PCM.

⇒	If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If circuit tests normal, replace the PCM.

5. Test the EVAP vent solenoid for correct operation. Refer to Evaporative Emission Control System Diagnosis.
6. If the vent solenoid and circuits test normal, test for the following conditions:

•	DTCs P2401 or P2402 are also set--Refer to DTC P2401 or P2402.

•	A blockage or restriction in the EVAP filter or passages between the filter and the EVAP canister

•	A faulty EVAP canister--Refer to Evaporative Emission Control System Diagnosis.

⇒	If all conditions are normal, replace the EVAP vacuum leak pump assembly.

Component Testing

1. Ignition OFF, disconnect the harness connector at the EVAP vent solenoid.
2. Test for 25-30 ohms at 20°C (68°F) between the control terminal 1 and the ignition 1 voltage terminal 2.

⇒	If not within the specified range, replace the EVAP purge solenoid.

3. Test for infinite resistance between each terminal and the EVAP purge solenoid housing.

⇒	If not the specified value, replace the EVAP purge solenoid.

4. Test the EVAP vent solenoid for correct operation. Refer to Evaporative Emission Control System Diagnosis.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Repair Verification

With Service Bay Test

Verify the EVAP system repair using the EVAP Service Bay Test. Refer to Service Bay Test.

Without Service Bay Test

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.