P0449

Circuit Description
Output Driver Modules (ODMs) are used by the PCM to turn on many of the current-driven devices that are needed to control various engine and Transmission functions. Each ODM is capable of controlling up to 7 separate outputs by applying ground to the device which the PCM is commanding ON. Unlike the Quad Driver Modules (QDMs) used in prior model years, ODMs have the capability of diagnosing each output circuit individually. DTC P0449 set indicates an improper voltage level has been detected on the output circuit which controls the EVAP Canister Vent Solenoid Valve.

Condition for Running the DTC
The ignition is ON.

Condition for Setting the DTC
^ An improper voltage level has been detected on the EVAP canister vent valve control circuit.
^ The above conditions are present for at least 30 seconds.

Action Taken When the DTC Sets
^ The PCM will illuminate the MIL during the second consecutive trip in which the diagnostic test has been run and failed.
^ The PCM will store conditions which were present when the DTC set as Freeze Frame and Fail Records data.

Conditions for Clearing the MIL/DTC
^ The PCM will turn the MIL OFF during the third consecutive trip in which the diagnostic has been run and passed.
^ The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
^ The DTC can be cleared by using a scan tool.

Diagnostic Aids
Check for the following conditions:
^ Poor connection at the PCM.
Inspect harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and poor terminal to wire connection.
^ Damaged harness.
^ Inspect the wiring harness for damage. If the harness appears to be OK, disconnect the PCM, turn the ignition ON and observe a voltmeter connected between the solenoid control circuit and ground at the PCM harness connector while moving connectors and wiring harnesses related to the solenoid. A change in voltage will indicate the location of the malfunction.

Review the Fail Records vehicle mileage since the diagnostic test last failed. This may help determine how often the condition that caused the DTC to be set occurs.

Test Description
The number(s) below refer to the step number(s) on the diagnostic table.
1. The Diagnostic System Check prompts you to complete some basic checks and store the freeze frame and failure records data on the scan tool.
2. Listen for an audible clicking when the Purge solenoid operates. Command both the Increase and Decrease states. Repeat the commands as necessary.
3. Tests for voltage at the feed side of the Purge solenoid.
4. Verifies that the PCM is providing ground to the Purge solenoid.
5. Tests if ground is constantly being applied to the Purge solenoid.
12. The PCM utilizes Electrically Erasable Programmable Read Only Memory (EEPROM). When the PCM is replaced, the new PCM must be programmed.