2010 Cadillac Truck SRX FWD V6-3.0L Page 1493
* No fuel filling during the engine off natural vacuum test period.
* The fuel level is between 10-90 percent.
* The start-up engine coolant temperature (ECT) and the start-up intake air temperature (IAT) are between 0-40掳C (32-104掳F).
* The barometric pressure (BARO) is more than 74 kPa.
* The engine run time before engine shut-off was greater than 10 minutes.
* The drive distance before engine shut-off was more than 5 kilometers (3.1 miles).
* The ignition is OFF.
* The ambient air temperature at the end of the drive cycle is between 0-32掳C (32-93掳F).
* DTC P0442 runs once per drive cycle during the hot soak period after the ignition is turned OFF and may require up to 45 minutes to
complete. The controller will not make more than 2 test attempts per day. The time since the last completed engine off natural vacuum test
must be at least 17 hours
Conditions for Setting the DTC
* The ECM detects a leak in the evaporative emission system that is greater than a calibrated amount.
* The ECM must complete several engine off natural vacuum tests before the diagnostic can turn the MIL on or off.
Action Taken When the DTC Sets
DTC P0442 is a Type A DTC.
Conditions for Clearing the DTC
DTC P0442 is a Type A DTC.
Diagnostic Aids
* The evaporative emission system can be filled with smoke more quickly and completely by opening the system opposite the end where the
smoke is injected. When injecting smoke at the service port remove the fuel fill cap, or temporarily leave the vent open, until smoke is
observed then close the system and continue testing.
* To help locate intermittent leaks using the J 41413-200 - EEST , move all evaporative emission components while observing smoke with the
J 41413-SPT - White Light.
* Individual components can be isolated and tested using adapters in the J 41413-300 - Kit.
* A condition may exist where a leak in the evaporative emission system only exists under a vacuum condition. This type of leak may be
detected by using the scan tool Purge/Seal function to create a vacuum in the evaporative emission system and then observe the fuel tank
pressure parameter for vacuum decay.
Reference Information
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions (See: Diagnostic Trouble Code Descriptions/Powertrain Diagnostic Trouble Code
(DTC) Type Definitions)
Description and Operation
Evaporative Emission Control System Description (See: Powertrain Management/Computers and Control Systems/Description and
Operation/Evaporative Emission Control System Description)
Scan Tool Reference
Control Module References (See: Testing and Inspection/Programming and Relearning)for scan tool information
Special Tools
* CH 48096 - Evaporative Emissions Service Access Port Tool
* J 41413-200 - Evaporative Emissions System Tester (EEST)
* J 41413-300 - Evaporative Emissions Cap and Plug Kit
* J 41413-SPT - High Intensity White Light
* For equivalent regional tools, refer to Special Tools (See: Powertrain Management/Computers and Control Systems/Tools and Equipment).
Circuit/System Testing
Note:
* Refer to the J 41413-200 - EEST operation manual for detailed instructions in Evaporative Emission System Diagnosis (See: Powertrain
Management/Computers and Control Systems/Testing and Inspection/Component Tests and General Diagnostics/Evaporative Emission
System Diagnosis).
* Larger volume fuel tanks and/or those with lower fuel levels may require several minutes for the floating indicator to stabilize.
* Ensure that the underbody temperature of the vehicle and the tester are similar.
1. Disconnect the purge tube at the quick connector on the evaporative emission canister side of the Q12 evaporative emission canister purge
solenoid valve and install the CH 48096 - Port Tool.
2. Connect the J 41413-200 - EEST to the CH 48096 - Port Tool.
3. Using a scan tool close the evaporative emission canister vent solenoid valve to seal the evaporative emission system.
