2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2082

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2082

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

P0455

DTC P0455

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 (EVAP) 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 EVAP 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 EVAP system. The ECM monitors the fuel tank pressure (FTP) 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 volts.

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

* The fuel level is between 15-85 percent.

* The engine coolant temperature (ECT) 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 EVAP purge solenoid valve, purge pipe, EVAP canister, or vapor pipe, can cause this DTC to set.

* The EVAP 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. If using a fuel cap adapter at the filler neck, use the J 41413-VLV at the service port to

allow the system to fill faster.

* To help locate intermittent leaks using the J 41413-200, move all EVAP components while observing smoke with the J 41413-SPT.

* Individual components can be isolated and tested using adapters in the J 41413-300.

* A condition may exist where a leak in the EVAP 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 EVAP system and then observe the FTP parameter for vacuum decay.