Diagnostic Aids
WARNING: This page is about a different car, the 2007 Hummer H2. However, it is still accessible from the selected car via links, so may be relevant.
Scan tool output controls, snapshot, and plot functions can help detect erratic sensor response. To look at the sensor signal under vacuum conditions, use snapshot and the purge/seal function to capture data while commanding purge to 20 percent, then plot the data to look for non-linear sensor operation. A similar inspection can be done for the pressure side of the sensor range by applying pressure with J 41413-200 Evaporative Emission System Tester (EEST) while taking a snapshot. See Special Tools . DO NOT exceed 5 inches H2O when applying pressure.
DTC P0454
| Step | Action | Yes | No |
|---|---|---|---|
| Schematic Reference: Evaporative Emissions Hose Routing Diagram
and Engine Controls Schematics Connector End View Reference: Powertrain Control Module Connector End Views or Engine Controls Connector End Views |
|||
| 1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle |
| 2 | Are DTCs P0442, P0446, P0452, P0453, or P0651 also set? | Go to Diagnostic Trouble Code (DTC) List - Vehicle | Go to Step 3 |
| 3 | Inspect for an intermittent and for a poor connection at the fuel tank pressure (FTP) sensor. Refer to Testing for Intermittent Conditions and Poor Connections
. Did you find and correct the condition? |
Go to Step 5 | Go to Step 4 |
| 4 | Replace the FTP sensor. Refer to Fuel Tank Pressure Sensor Replacement
. Did you complete the replacement? |
Go to Step 5 | - |
| 5 | Observe the Capture Info with a scan tool. Have any other DTCs not been diagnosed? |
Go to Diagnostic Trouble Code (DTC) List - Vehicle | System OK |