2010 Cadillac Truck SRX FWD V6-3.0L Page 1492

2010 Cadillac Truck SRX FWD V6-3.0L Page 1492

瀚慖f a condition is found, replace the catalytic converter.

3. Verify the following conditions do not exist with the exhaust system:

* Leaks

* Physical damage

* Loose or missing hardware

* Properly torqued HO2S

瀚慖f a condition is found, repair the exhaust system.

4. Verify the following conditions do not exist with the HO2S 2:

* A grounded wiring harness

* Damage

瀚慖f a condition is found, replace the HO2S 2.

5. If no physical condition is detected and the HO2S 2 is as active as the HO2S 1 after operating the engine at 1,500 RPM for 1 minute and then

returning to a stabilized idle, then replace the catalytic converter.

Repair Instructions

Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.

* Exhaust Leakage (See: Engine, Cooling and Exhaust/Exhaust System/Testing and Inspection/Exhaust Leakage)

* Restricted Exhaust (See: Engine, Cooling and Exhaust/Exhaust System/Testing and Inspection/Restricted Exhaust)

* Heated Oxygen Sensor Replacement - Bank 1 Sensor 2 (LF1) (See: Powertrain Management/Computers and Control Systems/Oxygen

Sensor/Service and Repair/Heated Oxygen Sensor Replacement - Bank 1 Sensor 2)

* Heated Oxygen Sensor Replacement - Bank 2 Sensor 2 (LF1) (See: Powertrain Management/Computers and Control Systems/Oxygen

Sensor/Service and Repair/Heated Oxygen Sensor Replacement - Bank 2 Sensor 2)

* Catalytic Converter Replacement - Left Side (LF1) (See: Engine, Cooling and Exhaust/Exhaust System/Catalytic Converter/Service and

Repair/Catalytic Converter Replacement - Left Side)

* Catalytic Converter Replacement - Right Side (LF1) (See: Engine, Cooling and Exhaust/Exhaust System/Catalytic Converter/Service and

Repair/Catalytic Converter Replacement - Right Side)

P0442

DTC P0442

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 P0442

- Evaporative Emission System Small Leak Detected

Circuit/System Description

The engine off natural vacuum test is the small leak detection diagnostic for the evaporative emission system. This diagnostic tests the evaporative

emission system for a small leak when the key is turned OFF and the correct conditions are met. Heat from the exhaust system is transferred into

the fuel tank while the vehicle is operating. When the vehicle is turned OFF and the evaporative emission system is sealed a change in the fuel tank

vapor temperature occurs which results in a corresponding pressure change in the fuel tank vapor space. This change is monitored by the ECM

using the fuel tank pressure sensor input. With a leak in the system, the amount of pressure change will be less than that of a sealed system.

Conditions for Running the DTC

* DTCs P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0222, P0223, P0443, P0446, P0449,

P0451, P0452, P0453, P0454, P0455, P0461, P0462, P0463, P0464, P0496, P0502, P0503, P0608, P0641, P0651, P1516, P2101, P2119,

P2120, P2122, P2123, P2125, P2127, P2128, P2135, P2138 are not set.

* The ignition 1 voltage is between 10-16 V.

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