SteveDR425

Hey guys,

I just had this code show up this morning. 10-PCM -P0449

I looked it up and got this description below (Not sure if it's correct).
DTC P0449 Evaporative Emission (EVAP) Vent Solenoid Control Circuit

Can anyone tell me what this means or how I can fix it? Don’t want to take it to the stealer ship unless I absolutely have to. Thanks!

SteveDR425

Bump!

Can anyone help? Is this something I can just clear off?

trussme

go here:

http://www.gearchatter.com/viewtopic10454.php

Bill Dearborn

Here is some info for you. Diagnostic Procedure and schematic.

DTC P0449

Circuit Description
An ignition voltage is supplied to the evaporative emission (EVAP) canister vent valve. The control module grounds the EVAP canister vent valve control circuit to close the valve by means of an internal switch called a driver. The scan tool displays the commanded state of the EVAP canister vent valve as ON or OFF. The control module monitors the status of the driver. If the control module detects an incorrect voltage for the commanded state of the driver, this DTC sets.
The following table illustrates the relationship between the ON and OFF states, and the OPEN or CLOSED states of the EVAP canister vent valve.
Control Module Command EVAP Canister Vent Valve Position
ON CLOSED
OFF OPEN

Conditions for Running the DTC
• The engine speed is more than 400 RPM.
• The system voltage is between 6-18 volts.

Conditions for Setting the DTC
• The control module detects that the commanded state of the driver and the actual state of the control circuit do not match.
• The above conditions are present for a minimum of 5 seconds.

Action Taken When the DTC Sets
• The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
• The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

Conditions for Clearing the MIL/DTC
• The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
• A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
• A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
• Clear the MIL and the DTC with a scan tool.

Test Description
The numbers below refer to the step numbers on the diagnostic table.

Step 2. A click should be heard or felt when the solenoid operates. Be sure that both the ON and the OFF states are commanded. Repeat the commands as necessary.

Step 5. This step verifies that the control module is providing ground to the EVAP canister vent solenoid.

Step 6. This step tests if the EVAP canister vent solenoid control circuit is grounded.

Step Action Yes No

Step 1
Did you perform the Diagnostic System Check-Engine Controls? Go to Step 2
Go to Diagnostic System Check - Engine Controls

Step 2
1. Turn ON the ignition, with the engine OFF.
2. Command the EVAP canister vent solenoid ON and OFF with a scan tool.
Do you hear or feel a click from the EVAP canister vent solenoid when it is commanded ON and OFF? Go to Step 3
Go to Step 4

Step 3
1. Observe the Freeze Frame / Failure Records for this DTC.
2. Turn OFF the ignition for 30 seconds.
3. Turn ON the ignition, with the engine OFF.
4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Did the DTC fail this ignition? Go to Step 4
Go to Intermittent Conditions

Step 4
1. Turn OFF the ignition.
2. Disconnect the EVAP vent solenoid.
3. Turn ON the ignition, with the engine OFF.
4. Probe the ignition 1 voltage circuit of the EVAP canister vent solenoid with a test lamp that is connected to a good ground. Refer to Troubleshooting with a Test Lamp .
Does the test lamp illuminate? Go to Step 5
Go to Step 11

Step 5
1. Connect a test lamp between the control circuit of the EVAP vent solenoid and the ignition 1voltage circuit of the EVAP vent solenoid. Refer to Troubleshooting with a Test Lamp .
2. Command the EVAP canister vent solenoid ON and OFF with a scan tool.
Does the test lamp turn ON or OFF with each command? Go to Step 9
Go to Step 6

Step 6
Does the test lamp remain illuminated with each command? Go to Step 8
Go to Step 7

Step 7
Test the control circuit for a short to voltage or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition? Go to Step 14
Go to Step 10

Step 8
Test the control circuit for a short to ground. Refer to Testing for Short to Ground and Wiring Repairs in Wiring Systems.
Did you find and correct the condition? Go to Step 14
Go to Step 10

Step 9
Test for an intermittent and for a poor connection at the EVAP vent solenoid. Refer to Testing for Intermittent and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition? Go to Step 14
Go to Step 12

Step 10
Test for an intermittent and for a poor connection at the control module. Refer to Testing for Intermittent and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition? Go to Step 14
Go to Step 13

Step 11
Repair the open or short to ground in the ignition 1 voltage circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Replace the fuse if necessary.
Did you complete the repair? Go to Step 14
--
Step 12
Replace the EVAP vent solenoid. Refer to Evaporative Emission (EVAP) Canister Vent Valve Replacement .
Did you complete the replacement? Go to Step 14
--
Step 13
Replace the control module. Refer to Powertrain Control Module (PCM) Replacement .
Did you complete the replacement? Go to Step 14
--
Step 14
1. Clear the DTCs with a scan tool.
2. Turn OFF the ignition for 30 seconds.
3. Start the engine.
4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Did the DTC fail this ignition? Go to Step 2
Go to Step 15

Step 15
Observe the Capture Info with a scan tool.
Are there any DTCs that have not been diagnosed? Go to Diagnostic Trouble Code (DTC) List
System OK





(1) Evaporative Emission (EVAP) Canister Vent Solenoid


Evaporative Emission (EVAP) Canister Vent Solenoid Valve Replacement

Removal Procedure

1. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
2. Lower the right muffler for automatic transmission equipped vehicles only. Refer to Muffler Replacement - Right in Engine Exhaust.

3. Disconnect the EVAP canister valve harness connector.
4. Disconnect the vent hose (2) from the EVAP canister vent valve (1).



5. Remove the EVAP canister vent valve (2) from the vent bracket (1).




Installation Procedure
1. Install the EVAP canister vent valve (2) to the vent bracket (1).



Connect the vent hose (2) to the EVAP canister vent valve (1).



2. Connect the EVAP vent valve electrical connector.
3. For automatic transmission- equipped vehicles only, raise the right muffler. Refer to Muffler Replacement - Right in Engine Exhaust.
4. Lower the vehicle.




Bill

Jhaintz1980

Thanks for the great info Bill!

turbo87

This just helped me also.Thanks

volleybill

Hmm, wonder if this thread can be resurrected? This was great info and drawings, made my life a whole lot easier when I replaced my 10-year old vent solenoid on my 2008- thanks!

walleyejack

no, it can t be