2010 Cadillac CTS Sedan AWD V6-3.6L Page 1461
3. Compare the scan tool Fuel Tank Pressure sensor parameter to the J 41413-200 pressure/vacuum gauge. The scan tool FTP sensor
parameter should be within 1.86 mm/Hg (1 in H20) of the pressure/vacuum gauge.
4. Command the EVAP vent valve open with a scan tool. The scan tool Fuel Tank Pressure parameter should be approximately 0 mm/Hg (0 in
H20).
瀚慖f not within the specified range, replace the FTP sensor.
Repair Instructions
* Fuel Tank Pressure Sensor Replacement (See: Powertrain Management/Computers and Control Systems/Fuel Tank Pressure Sensor/Service
and Repair)
* Evaporative Emission Canister Purge Solenoid Valve Replacement (LF1) (See: Powertrain Management/Emission Control
Systems/Evaporative Emissions System/Canister Purge Solenoid/Service and Repair)Evaporative Emission Canister Purge Solenoid Valve
Replacement (LLT) (See: Powertrain Management/Emission Control Systems/Evaporative Emissions System/Canister Purge
Solenoid/Service and Repair)
* Evaporative Emission Canister Vent Solenoid Valve Replacement (See: Powertrain Management/Emission Control Systems/Evaporative
Emissions System/Evaporative Emission Control Canister/Canister Vent Valve/Service and Repair)
* Evaporative Emission Line Replacement - Chassis to Canister (See: Powertrain Management/Emission Control Systems/Evaporative
Emissions System/Evaporative Emissions Hose/Service and Repair)
* Evaporative Emission Canister Replacement (See: Powertrain Management/Emission Control Systems/Evaporative Emissions
System/Evaporative Emission Control Canister/Service and Repair)
Repair Verification
1. Turn the nitrogen/smoke valve to nitrogen.
2. Command the EVAP vent valve closed with a scan tool.
3. Use the remote switch to activate the J 41413-200 .
4. Use the remote switch to introduce nitrogen and fill the EVAP system until the floating indicator stabilizes.
5. Verify the flow meter's stable floating indicator position is at or below the red flag.
6. Remove the CH-48096 , and connect the purge line to the EVAP purge solenoid.
7. Clear the DTCs with a scan tool.
P0498
DTC P0449, P0498, or P0499 (w/LLT)
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System
Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an
overview of the diagnostic approach.
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC P0449
- Evaporative Emission (EVAP) Vent Solenoid Control Circuit
DTC P0498
- Evaporative Emission (EVAP) Vent Solenoid Valve Control Circuit Low Voltage
DTC P0499
- Evaporative Emission (EVAP) Vent Solenoid Valve Control Circuit High Voltage
Diagnostic Fault Information
Circuit/System Description
The evaporative emission (EVAP) canister vent valve is used for EVAP system diagnostics. The EVAP canister vent valve is a normally open
valve. Battery positive voltage is supplied directly to the EVAP canister vent valve. The engine control module (ECM) controls the solenoid by
grounding the control circuit with a solid state device called a driver. The driver is equipped with a feedback circuit that is pulled-up to a voltage.
