2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1346

2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1346

Control Module References (See: Testing and Inspection/Programming and Relearning)for scan tool information

Circuit/System Testing

1. Engine idling, observe the DTC information with a scan tool. Verify there are no HO2S or misfire DTCs set.

瀚慖f any of the DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle (See: Diagnostic Trouble Code

Descriptions/Diagnostic Trouble Code (DTC) List - Vehicle) to diagnosis the applicable DTC, before proceeding with this diagnostic

procedure.

2. Verify the following conditions do not exist with the catalytic converter:

* Dents

* A severe discoloration caused by excessive temperatures

* Road damage

* An internal rattle caused by damaged catalyst substrate

* Restrictions

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) ()

* Heated Oxygen Sensor Replacement - Bank 2 Sensor 2 (LF1) ()

* Catalytic Converter Replacement - Left Side (LF1) ()

* Catalytic Converter Replacement - Right Side (LF1) ()

P0430

DTC P0420 or P0430

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 P0420

- Catalyst System Low Efficiency Bank 1