2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1372

2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1372

Solenoid/Service and Repair)

* Evaporative Emission Canister Vent Solenoid Valve Replacement (NT7, NU5) (See: Powertrain Management/Emission Control

Systems/Evaporative Emissions System/Evaporative Emission Control Canister/Canister Vent Valve/Service and Repair)

* Evaporative Emission Canister Replacement (NT7, NU5) (See: Powertrain Management/Emission Control Systems/Evaporative Emissions

System/Evaporative Emission Control Canister/Service and Repair)

Repair Verification

1. Seal the evaporative emission system and use the flow meter on the J 41413-200 - EEST , calibrated to 0.51 mm (0.020 in) to determine that

there is no leak in the evaporative emission system.

2. Clear DTCs.

P0458

DTC P0443, P0458, or P0459 (LAU)

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 P0443

- Evaporative Emission (EVAP) Purge Solenoid Control Circuit

DTC P0458

- Evaporative Emission (EVAP) Purge Solenoid Control Circuit Low Voltage

DTC P0459

- Evaporative Emission (EVAP) Purge Solenoid Control Circuit High Voltage

Diagnostic Fault Information

Circuit/System Description

The evaporative emission (EVAP) canister purge valve is used to purge fuel vapor from the EVAP canister to the intake manifold. The EVAP

canister purge valve is pulse width modulated (PWM). Ignition voltage is supplied directly to the EVAP canister purge 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. The ECM can determine if the control circuit is open, shorted to ground, or shorted to a voltage by

monitoring the feedback voltage.

Conditions for Running the DTC

* The engine speed is greater than 80 RPM.

* The ignition voltage is between 10-18 volts.

* The ECM has commanded the EVAP canister purge valve ON and OFF at least once during the ignition cycle.

* The DTCs run continuously once the above conditions are met.

Conditions for Setting the DTC

P0443

The ECM detects the EVAP canister purge solenoid control circuit is open. The condition exists for 4 seconds or a cumulative of 30 seconds.

P0458

The ECM detects the EVAP canister purge solenoid control circuit is shorted to ground. The condition exists for 4 seconds or a cumulative of 30