2010 Cadillac Truck SRX AWD V6-3.0L Page 1511

2010 Cadillac Truck SRX AWD V6-3.0L Page 1511

* Fuel Tank Pressure Sensor Replacement (See: Powertrain Management/Computers and Control Systems/Fuel Tank Pressure Sensor/Service

and Repair)

* For DTC P0452 or P0453, always perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic

procedure.

* For DTC P0451 or P0454, clear DTCs with a scan tool.

* Control Module References (See: Testing and Inspection/Programming and Relearning) for ECM replacement, setup, and programming

P0455

DTC P0455 (LF1)

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 Descriptor

DTC P0455

- Evaporative Emission System Large Leak Detected

Circuit/System Description

The ECM tests the evaporative emission (EVAP) system for a large leak or restrictions to the purge path in the evaporative emission system. When

the enabling criteria has been met the ECM commands the EVAP canister vent solenoid valve ON and the EVAP canister purge solenoid valve ON,

allowing vacuum into the evaporative emission system. The ECM monitors the fuel tank pressure sensor voltage to verify that the system is able to

reach a predetermined level of vacuum within a set amount of time.

Conditions for Running the DTC

* Before the ECM can report DTC P0455 failed, DTC P0496 must run and pass.

* DTCs P0106, P0107, P0108, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0220, P0222, P0223, P0442, P0443, P0449, P0451,

P0452, P0453, P0454, P0464, P0496, P0608, P0609, P0641, P0651, P1516, P2101, P2119, P2120, P2122, P2123, P2125, P2127, P2128,

P2135, P2138 are not set.

* The ignition voltage is between 11-18 V.

* The barometric pressure (BARO) is more than 74 kPa.

* The fuel level is between 10-90 percent.

* The engine coolant temperature (ECT) at start-up is less than 35掳C (95掳F).

* The intake air temperature (IAT) is between 4-30掳C (39-86掳F).

* DTC P0455 runs once per cold start when the above conditions are met.

Conditions for Setting the DTC

The EVAP system is not able to achieve or maintain a calibrated level of vacuum within a set amount of time.

Action Taken When the DTC Sets

DTC P0455 is a Type B DTC.

Conditions for Clearing the MIL/DTC

DTC P0455 is a Type B DTC.

Diagnostic Aids

* Inspect for a loose, missing, damaged, or incorrect fuel fill cap.

* Inspect for a damaged fuel filler neck seal surface.

* A blockage or restriction in the evaporative emission purge solenoid valve, purge pipe, evaporative emission canister, or vapor pipe, can

cause this DTC to set.

* 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. For example, 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.